v4l2videodec : enable dynamic resolution change

The dynamic resolution changes when the sequence starts when the decoder detects a coded frame with one or more of the following parameters different from those previously established (and reflected by corresponding queries): 1.coded resolution (OUTPUT width and height), 2.visible resolution (selection rectangles), 3.the minimum number of buffers needed for decoding, 4.bit-depth of the bitstream has been changed.

Although gstreamer parser has parsed the stream resolution. but there are some case that we need to handle resolution change event.

1. bit-depth is different from the negotiated format.
2. the capture buffer count can meet the demand
3. there are some hardware limitations that the decoded resolution may be larger than the display size. For example, the stream size is 1920x1080, but some vpu may decode it to 1920x1088.