msm: audio: initialize the structure before sending to user space

If uninitialzied structure is passed from kernel to user space, it
may contain sensitive information that will be leaked.

Change-Id: Ie7c4568c78df8cbd1efeff559848058c2163b0b8
Signed-off-by: Fred Oh <fred@codeaurora.org>
Signed-off-by: Ajay Dudani <adudani@codeaurora.org>

Conflicts:
	arch/arm/mach-msm/qdsp5/audio_aac.c