Change to handle A2dp suspend setparameter, which will suspend the thread

When A2dp suspend setparameter is called we were not suspending the thread.
We were suspending it only during stop. This will make sure we suspend the
thread even during the suspend setparameter call

CRs-Fixed: 415399
Change-Id: I49ae25fc028e9d4927fd3d3131c8f97f3e873fc1
alsa_sound: Fix corruption in recording over usb.

-Sometimes the hardware pointer for proxy driver is not updated for
 successive callbacks. This is because in the recording case proxy
 driver and usb driver runs at real time. This does not mandate
 that the data is read by proxy driver as soon as data is written
 from userspace. Any delay in getting dat from usb also can cause
 the issue.
-Fix is to increase the start threshold of proxy side for recording
 so that playback is not started without sufficient data.

Change-Id: I86384bfc96b8262309a1402ca9fe5744af3b436d
CRs-Fixed: 465317