msm: Fix high load average from uninterruptible waits

 * The load average on all MSMs is currently hovering at around 14
   due to uninterruptible waits in various places.
 * Convert these waits to interruptible waits to bring the load
   back down to zero at idle.

Signed-off-by: flar2 <asegaert@gmail.com>

Change-Id: I14bad4af135b1594e235e2252cb484cb34d91054