H264 FEI support

H264 FEI support

The purpose of FEI (Flexible Encoding Infrastructure) is to allow applications
to have more controls and trade off quality for speed with their own IPs. The
application can optionally provide input to ENC for extra encode control and
get the output from ENC. Application can chose to modify the ENC output/PAK
input during encoding, but the performance impact is significant.

FEI EntryPoint/BufferType/Attrib changes are in va.h, codec common
changes are in va_fei.h, va_fei_h264.h is for H264 special changes

Signed-off-by: Kelvin Hu <kelvin.hu@intel.com>
Signed-off-by: Jonathan Bian <jonathan.bian@intel.com>
Signed-off-by: Xiang, Haihao <haihao.xiang@intel.com>
Signed-off-by: Sreerenj Balachandran <sreerenj.balachandran@intel.com>
Signed-off-by: Zhong Li <zhong.li@intel.com>
Signed-off-by: Daniel Charles <daniel.charles@intel.com>