To build Netflix with Rialto, OCDM setting has to be enabled in netflix bitbake:

diff --git a/recipes-extended/netflix/netflix_5.1.bb b/recipes-extended/netflix/netflix_5.1.bb
index d56fee8..402127f 100644
--- a/recipes-extended/netflix/netflix_5.1.bb
+++ b/recipes-extended/netflix/netflix_5.1.bb
@@ -42,12 +42,12 @@ SRCREV_netflix = "${AUTOREV}"
 S = "${WORKDIR}/git/netflix"
 BBCLASSEXTEND = "native"
  
-DEPENDS += " gstreamer1.0 python-native freetype icu jpeg libpng libmng libwebp harfbuzz libnl nghttp2 expat openssl c-ares curl curl-netflix graphite2 util-linux glib-2.0 iarmmgrs cjson tremor libogg systemd nodejs-native wayland essos pxcore-libnode"
+DEPENDS += " gstreamer1.0 python-native freetype icu jpeg libpng libmng libwebp harfbuzz libnl nghttp2 expat openssl c-ares curl curl-netflix graphite2 util-linux glib-2.0 iarmmgrs cjson tremor libogg systemd nodejs-native wayland essos pxcore-libnode rialto rialto-ocdm"
 DEPENDS +=  "${@bb.utils.contains('DISTRO_FEATURES', 'enable_icrypto_mgk', 'wpeframework-clientlibraries', '', d)}"
 DEPENDS +=  "${@bb.utils.contains('DISTRO_FEATURES', 'rdk_svp', 'gst-svp-ext', '', d)}"
 DEPENDS +=  "${@bb.utils.contains('DISTRO_FEATURES', 'netflix_drm_PR4', 'playready-cdm-rdk', 'playready', d)}"
  
-RDEPENDS_${PN} += "devicesettings"
+RDEPENDS_${PN} += "devicesettings  rialto rialto-ocdm"
 RDEPENDS_${PN} += "${@bb.utils.contains('DISTRO_FEATURES', 'rdk_svp', 'gst-svp-ext', '', d)}"
  
 ### Downloadable Application Package
@@ -87,7 +87,7 @@ EXTRA_OECMAKE_append_dunfell = "${@bb.utils.contains('DISTRO_FEATURES', 'ssl-1.1
 #Configure the DRM connected to the Netflix app
 PR4_DRM = "${@bb.utils.contains('DISTRO_FEATURES', 'netflix_drm_PR4', 1, 0, d)}"
 PR_DRM =  "${@ "rdkplayready4" if ${PR4_DRM} else "playready" }"
-OCDM = "${@bb.utils.contains('DISTRO_FEATURES', 'netflix_drm_ocdm', 1, 0, d)}"
+OCDM = "1"
  
 NETFLIX_DRM = "${@ "ocdm" if ${OCDM} else "${PR_DRM}" }"
 DEPENDS += "${@ " wpeframework rdkservices rdkservices-comcast"  if ${OCDM} else "" }"
@@ -344,6 +344,8 @@ EXTRA_OECMAKE += " \
     -DNRDP_HAS_PARTNER_INTEGRATION_SET_COOKIE=1 \
     -DUSE_GST_PLAYBIN=${ENABLE_NETFLIX_PLUGIN} \
     -DENABLE_GENERIC_PORT=${ENABLE_NETFLIX_PLUGIN} \
+    -DUSE_AUDIOMIXER_GST=1 \
+    -DUSE_RIALTO_AUDIO_SINK=1 \
     -DCURL_LIB="${STAGING_LIBDIR}/netflix/libcurl.a" \
     -DUSE_CURL_NETFLIX=1"

When netflix is built, couple of files have to be modified to disable westeros sink and to use rialto-ocdm instead of real ocdm:

diff --git a/partner/dpi/gstreamer/PlaybackGroupNativeGenericPort.cpp b/partner/dpi/gstreamer/PlaybackGroupNativeGenericPort.cpp
index 0e18186f..6d87f825 100644
--- a/partner/dpi/gstreamer/PlaybackGroupNativeGenericPort.cpp
+++ b/partner/dpi/gstreamer/PlaybackGroupNativeGenericPort.cpp
@@ -175,7 +175,7 @@ PlaybackGroupNativeGenericPort::PlaybackGroupNativeGenericPort(ESManagerNative&
     g_object_set(mGstPipeline, "audio-filter", capsfilter, NULL);
   }
  
-  GstElement* videoSinkGst = createWesterosSink();
+  // GstElement* videoSinkGst = createWesterosSink();
  
 #if defined(GST_GL)
   mVideoSinkGst.reset(new VideoSinkGStreamer());
@@ -1354,7 +1354,7 @@ void PlaybackGroupNativeGenericPort::updateVideoRectangle(bool force)
   GstElement* videoSink = GstUtilities::findElement(mGstPipeline, VIDEO_SINK_NAME);
   if (!videoSink)
   {
-    Log::error (TRACE_MEDIAPLAYBACK, "vSink not present");
+    // Log::error (TRACE_MEDIAPLAYBACK, "vSink not present");
     return;
   }
  
diff --git a/partner/dpi/gstreamer/drm.cmake b/partner/dpi/gstreamer/drm.cmake
index 543c7a84..b6b497c1 100644
--- a/partner/dpi/gstreamer/drm.cmake
+++ b/partner/dpi/gstreamer/drm.cmake
@@ -293,7 +293,7 @@ elseif(DPI_DRM STREQUAL "ocdm")
         add_definitions( -DSEC_BCOM_ENABLE_RAAGA )
         add_definitions( -DSEC_TARGET_PACEXI3 )
         add_definitions( -DSEC_PLATFORM_BCOM -DSEC_BCOM_INIT_NXCLIENT -DSEC_BCOM_ENABLE_SECURERSA -DSEC_BCOM_ENABLE_ADOBEBIN -DSEC_BCOM_ENABLE_HWHMAC -DSEC_BCOM_ENABLE_HWDIGEST -DSEC_BCOM_ENABLE_MKR -DUSE_NXCLIENT -fPIC)
-        target_link_libraries(nrddpi ocdm sec_api)
+        target_link_libraries(nrddpi ocdmRialto sec_api)
     elseif(DEFINED SECAPI_ENGINE_BROADCOM_SAGE)
     # Broadcom SAGE
         add_definitions( -DUSE_SECAPI_BRCMHW=1 )
@@ -304,21 +304,21 @@ elseif(DPI_DRM STREQUAL "ocdm")
         if (DEFINED SAGE_SVP)
             add_definitions (-DUSE_SAGE_SVP)
         endif()
-        target_link_libraries(nrddpi ocdm sec_api)
+        target_link_libraries(nrddpi ocdmRialto sec_api)
     elseif(DEFINED SECAPI_ENGINE_REALTEK)
             add_definitions( -DUSE_SECAPI_HW=1 )
-            target_link_libraries(nrddpi ocdm sec_api)
+            target_link_libraries(nrddpi ocdmRialto sec_api)
     elseif(DEFINED SECAPI_ENGINE_AMLOGIC)
         add_definitions( -DUSE_SECAPI_HW=1 )
-        target_link_libraries(nrddpi playready ocdm sec_api)   
+        target_link_libraries(nrddpi playready ocdmRialto sec_api)   
     elseif(DEFINED SECAPI_ENGINE_CRYPTANIUM)
     # Cryptanium
         add_definitions( -DUSE_SECAPI_CRYPTANIUM=1 )
-        target_link_libraries(nrddpi ocdm sec_api_crypto)
+        target_link_libraries(nrddpi ocdmRialto sec_api_crypto)
     else()
     # OpenSSL
         add_definitions( -DUSE_SECAPI_OPENSSL=1 )
-        target_link_libraries(nrddpi ocdm sec_api yajl)
+        target_link_libraries(nrddpi ocdmRialto sec_api yajl)
     endif(DEFINED SECAPI_ENGINE_BROADCOM_RAAGA)
  
     add_definitions( -DOCDM )

After modifications of those files, bitbake -C configure netflix has to be executed.