ASoC: msm: avoid negative time stamp check

Time stamp is unsigned. There is no need to check for
negative value.

Change-Id: Ibd163a43cdfdb056e6ed775799fb709def9733df
CRs-fixed: 423372
Signed-off-by: Patrick Lai <plai@codeaurora.org>
diff --git a/include/sound/q6asm.h b/include/sound/q6asm.h
index ab75bff..42c9120 100644
--- a/include/sound/q6asm.h
+++ b/include/sound/q6asm.h
@@ -1,4 +1,4 @@
-/* Copyright (c) 2010-2012, Code Aurora Forum. All rights reserved.
+/* Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -332,7 +332,7 @@
 /* Enable Mute/unmute flag */
 int q6asm_set_mute(struct audio_client *ac, int muteflag);
 
-uint64_t q6asm_get_session_time(struct audio_client *ac);
+int q6asm_get_session_time(struct audio_client *ac, uint64_t *tstamp);
 
 /* Client can set the IO mode to either AIO/SIO mode */
 int q6asm_set_io_mode(struct audio_client *ac, uint32_t mode);