MLK-19274: drm: imx: dcss: add rotation functionality

MLK-19274: drm: imx: dcss: add rotation functionality

This patch will allow userspace to rotate planes by setting the
'rotation' property. Generally, 0 and 180 rotations are allowed for
pretty much all 8-bit xRGB and 2-plane YUV420 formats. 90/270 rotations
can be performed only for non-compressed tiled GPU xRGB formats. Tiled
YUV420 formats do not allow rotations at all because these formats need
DTRC for de-tiling and DTRC has no rotation support.

For more info, consult the DPR Features chapter in the reference manual.

Test example:

modetest -M imx-drm -w 27:rotation:4 -w 32:rotation:33 -w 27:alpha:30 -s
42@31:3840x2160-60@XR24 -P 32@31:3840x2160@NV21

The above will perform:
 * 180 degree rotation of primary plane (XR24);
 * vertical flip of first overlay plane (rotate-0 | reflect-y);
 * set primary plane alpha to 30;

Signed-off-by: Laurentiu Palcu <laurentiu.palcu@nxp.com>