omx: add OMX_IndexParamConsumerUsageBits

This is used by framework to query buffer consumers (e.g. video encoders)
about required usage bits.

Bug: 13222807
Change-Id: I508335c9d753c7a7224bb882f2228bd2f4144031
diff --git a/include/media/openmax/OMX_AsString.h b/include/media/openmax/OMX_AsString.h
index 65eb562..ae8430d 100644
--- a/include/media/openmax/OMX_AsString.h
+++ b/include/media/openmax/OMX_AsString.h
@@ -524,6 +524,7 @@
         case OMX_IndexConfigAutoFramerateConversion:    return "ConfigAutoFramerateConversion";
         case OMX_IndexConfigPriority:                   return "ConfigPriority";
         case OMX_IndexConfigOperatingRate:              return "ConfigOperatingRate";
+        case OMX_IndexParamConsumerUsageBits:           return "ParamConsumerUsageBits";
         default:                                        return asString((OMX_INDEXTYPE)i, def);
     }
 }