hal: add timestamp mode support for offload playback streams

Add timestamp mode support for offload playback streams.
Support is added through compressed path, which is configured
internally when timestamp mode is requested.

CRs-fixed: 2016014
Change-Id: I0cc982a51f87abed40e424bc31fe9e013342bb71
diff --git a/hal/audio_extn/utils.c b/hal/audio_extn/utils.c
index 27bbae8..669bdb4 100644
--- a/hal/audio_extn/utils.c
+++ b/hal/audio_extn/utils.c
@@ -111,6 +111,7 @@
     STRING_TO_ENUM(AUDIO_OUTPUT_FLAG_INCALL_MUSIC),
 #endif
     STRING_TO_ENUM(AUDIO_OUTPUT_FLAG_COMPRESS_PASSTHROUGH),
+    STRING_TO_ENUM(AUDIO_OUTPUT_FLAG_TIMESTAMP),
     STRING_TO_ENUM(AUDIO_INPUT_FLAG_NONE),
     STRING_TO_ENUM(AUDIO_INPUT_FLAG_FAST),
     STRING_TO_ENUM(AUDIO_INPUT_FLAG_HW_HOTWORD),