Adding Opus related struct definitions to OMX_Index

Adding Opus related structure and constant definitions to
OMX_Index.h

Change-Id: Iae0394c86900f0db322893ffce695f854624833a
diff --git a/include/media/openmax/OMX_IndexExt.h b/include/media/openmax/OMX_IndexExt.h
index c47a885..ffcd4f3 100644
--- a/include/media/openmax/OMX_IndexExt.h
+++ b/include/media/openmax/OMX_IndexExt.h
@@ -58,6 +58,7 @@
     /* Audio parameters and configurations */
     OMX_IndexExtAudioStartUnused = OMX_IndexKhronosExtensions + 0x00400000,
     OMX_IndexParamAudioAndroidAc3,                  /**< reference: OMX_AUDIO_PARAM_ANDROID_AC3TYPE */
+    OMX_IndexParamAudioAndroidOpus,                 /**< reference: OMX_AUDIO_PARAM_ANDROID_OPUSTYPE */
 
     /* Image parameters and configurations */
     OMX_IndexExtImageStartUnused = OMX_IndexKhronosExtensions + 0x00500000,