va: Move the usage hint logic to a common place
After modifiers enabled, we find the command such as:
gst-launch-1.0 -vf videotestsrc num-buffers=100 ! vapostproc ! "video/x-raw(memory:DMABuf),drm-format=AR24:0x0100000000000002" ! vapostproc ! "video/x-raw(memory:DMABuf),drm-format=NV12:0x0100000000000002" ! glimagesink
prints out error and fails to work.
The root cause is that we use different the usage hints for detecting the modifiers and for the real run time. So we should move the usage hint logic to some common place to avoid this.
Edited by He Junyan