API: add support for buffer exports.

Add interfaces for low-level buffer exports to suport interop with
external APIs like EGL or OpenCL (OCL). Theory of operations:

- vaAcquireBufferHandle(): locks buffer for external API usage. This
  is a synchronization point. Upon successful return, useful buffer
  details are returned in a somewhat implementation-specific way to
  support interop with external APIs.

- vaReleaseBufferHandle(): unlocks buffer after usage from external
  API, and deallocates any resources that were needed.

Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
HEVC: rename VADecPictureParameterBufferHEVC to VAPictureParameterBufferHEVC

Like as other codec, append a suffix of HEVC to VAPictureParameterBuffer for decoding

Signed-off-by: Xiang, Haihao <haihao.xiang@intel.com>
Move vaQueryProcessingRate() to the end of VADriverVTable

We should add the new hook function at the end of VADriverVTable,
Otherwise we are likely to meet the following compatibility issue.

libva info: Found init function __vaDriverInit_0_34
libva error: No valid vtable entry for vaQuerySurfaceStatus
libva error: /opt/X11R7/lib/dri/i965_drv_video.so init failed
libva info: va_openDriver() returns -1
vaInitialize failed with error code -1 (unknown libva error),exit

Signed-off-by: Xiang, Haihao <haihao.xiang@intel.com>
Signed-off-by: Chen, Wei-fu <wei-fu.chen@intel.com>
Change the definition of the buffer used for processing
rate query for encode/decode

Signed-off-by: Chen, Wei-fu <wei-fu.chen@intel.com>
Add VPP format and resolution query.
ROI updates for encoder.
Add dirty ROI indication for encoder.