drm/fourcc: Add formats for packed YUV 4:4:4 AVUY and XVUY permutations

Add FourCCs for two missing permutations of the packed YUV 4:4:4 color
components, namely AVUY and XVUY.

These formats are needed by the NXP i.MX8 ISI. While the ISI is
supported by a V4L2 device (corresponding formats have been submitted to
V4L2), it is handled in userspace by libcamera, which uses DRM FourCCs
for pixel formats.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20220616185210.22018-1-laurent.pinchart@ideasonboard.com