[media] v4l: subdev: Unify argument validation across IOCTLs
[media] v4l: subdev: Unify argument validation across IOCTLs

Separate validation of different argument types. There's no reason to do
this separately for every IOCTL.

Signed-off-by: Sakari Ailus <8d98c2be02a446df653daa2c00496b87f3f016e4@linux.intel.com>
Signed-off-by: Laurent Pinchart <3ded2f39a78f0d7044839546f95841842b4d7c96@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <0cae1d1e981e84d16b82ca3d17be8a7f826608d3@samsung.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs