drm/msm/dpu: add DRM_MODE_ROTATE_180 back to supported rotations

DRM_MODE_ROTATE_180 was previously marked as supported even
for devices not supporting inline rotation.

This is true because the SSPPs can always flip the image.

After inline rotation support changes, this bit was removed
and kms_rotation_crc IGT test starts skipping now whereas
it was previously passing.

Restore DRM_MODE_ROTATE_180 bit to the supported rotations
list.

Fixes: dabfdd8 ("add inline rotation support for sc7280")
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Tested-by: Jessica Zhang <quic_jesszhan@quicinc.com> # Trogdor (SC8170)
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/485928/
Link: https://lore.kernel.org/r/20220511222710.22394-1-quic_abhinavk@quicinc.com
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>

Author: Abhinav Kumar

drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c

@@ -1577,7 +1577,7 @@ struct drm_plane *dpu_plane_init(struct drm_device *dev,
 			BIT(DRM_MODE_BLEND_PREMULTI) |
 			BIT(DRM_MODE_BLEND_COVERAGE));
 
-	supported_rotations = DRM_MODE_REFLECT_MASK | DRM_MODE_ROTATE_0;
+	supported_rotations = DRM_MODE_REFLECT_MASK | DRM_MODE_ROTATE_0 | DRM_MODE_ROTATE_180;
 
 	if (pdpu->pipe_hw->cap->features & BIT(DPU_SSPP_INLINE_ROTATION))
 		supported_rotations |= DRM_MODE_ROTATE_MASK;