Fix for segfault on VP8 stream close

Fixed a seg fault in DestroySurfaces call in
the wrapper during VP8 stream close.

Signed-off-by: Sameer Kibey <sameer.kibey@intel.com>
use LIST_FOR_EACH_ENTRY_SAFE in DestroySurfaces

it fixes the infinite loop in DestroySurfaces,
fix vp8vldemo hang during exit

Change-Id: I16a7f60409d575da6aaf98d246f15a631aeeda41