DecoderInterface: remove surface pool related dead code
common: add lock and condition wrapper
decsurfacepool: refacting to remove unused functions
decoder: h264: modify into the right function name.

Signed-off-by: Zhong Cong <congx.zhong@intel.com>
tests: add encoder for h264 format.

Signed-off-by: Zhong Cong <congx.zhong@intel.com>
tests: add h264encode.cpp to Makefile.am

Signed-off-by: Zhong Cong <congx.zhong@intel.com>