G1 plugin capabilities: adds simple sink CAPS query function
G1 plugin capabilities: adds simple sink CAPS query function

It seems that G1 plugin didn't reply capabilities negotiation "CAPS query" when
supported formats between h264parser's src pad and g1h264dec's sink pad are
checked.
This was leading to a situation where resolution requirement from
drmsink was propagated to h264parser.

This adds a simple sink query function to the G1 plugin.

Signed-off-by: Juha Ylinen <58e95ab10d193f3c9b9eb43655bf3186926597d3@verisilicon.com>

linux4sam/gst1-hantro-g1,linux4sam/gst1-hantro-g1