msm: vidc: eliminate race condition in dynamic buffer mode

Function get_same_fd_buffer returned a pointer to
registered buffer, which shared the same fd as the
current buffer being mapped. While this buffer was
being accessed in map_and_register_buf(), it was
not guarded by the inst lock. So if the buffer was
erroneously freed, while it's still being accessed
in map_and_register_buf(), we may see a kernel
panic due to garbage values. To avoid this race
condition, introduce more checks in get_same_fd_buffer()
and return only the required handle information back to
map_and_register_buf.

Change-Id: I798c33dc344977c5db3bd74e5f863ca5cda14cb9
Signed-off-by: Arun Menon <avmenon@codeaurora.org>
msm: vidc: add LTR support for video encoder

Enable LTR support for VP8 codec to add robust error resilience.

Change-Id: I3b87c5cdaef836a6d02d5b9fe71b7165b7f13581
Signed-off-by: Ashray Kulkarni <ashrayk@codeaurora.org>
msm: vidc: Add generic LTR mode support

Use generic LTR HFI APIs for h264 and vp8 formats.

Change-Id: I9f307046d7ec6de4eb6d43704686be902356882a
Signed-off-by: Ashray Kulkarni <ashrayk@codeaurora.org>
msm: vidc: Add support to request frame level QP information

The resulting QP information for H264 is the slice level
QP averaged over whole frame; for all other codecs its
frame level QP.

Change-Id: I288904b05d886c1e94fc113b8bd3fba5b13b48f3
Signed-off-by: Jorge Solano Altamirano <jsolano@codeaurora.org>