media: hantro: Refactor for V4L2 API spec compliancy

Refactor how S_FMT and TRY_FMT are handled, and also make sure
internal initial format and format reset are done properly.

The latter is achieved by making sure the same hantro_{set,try}_fmt
helpers are called on all paths that set the format (which is
part of the driver state).

This commit removes the following v4l2-compliance warnings:

test VIDIOC_G_FMT: OK
	fail: v4l2-test-formats.cpp(711): Video Capture Multiplanar: TRY_FMT(G_FMT) != G_FMT
test VIDIOC_TRY_FMT: FAIL
	fail: v4l2-test-formats.cpp(1116): Video Capture Multiplanar: S_FMT(G_FMT) != G_FMT
test VIDIOC_S_FMT: FAIL

Reported-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>