frontends/va: make vlVaSyncSurface blocking
What does this MR do and why?
frontends/va: make vlVaSyncSurface blocking
According to VA documentation, vaSyncSurface should block,
so this mapping function vlVaSyncSurface is changed to be blocking.
add vlVaSyncSurface2 which can be used as non-blocking version.
Signed-off-by: David (Ming Qiang) Wu <David.Wu3@amd.com>