DO NOT MERGE audioflinger: dont release wakelock during offload drain sequence

workaround to avoid lost offload audio buffers during a compress_drain
when a wakelock is not held.
reference internal commit# 078538cf

Change-Id: I91fe76f985dfb619610f92f946022184564598cb
Signed-off-by: Sridhar Vashist <svashist@motorola.com>