media: imx-pxp: Add rotation support

PXP allows clockwise rotation of 0°, 90°, 180° and 270°.

Add support for it.

Tested on a imx6ull-evk.

For example, to rotate 90° the following Gstreamer pipeline can
be used:

gst-launch-1.0 videotestsrc ! video/x-raw,width=640,height=480 ! \
v4l2convert extra-controls=cid,rotate=90  ! \
video/x-raw,width=120,height=160 ! fbdevsink

Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>