[PATCH v5 2/2] drm/mali-dp: Implement plane alpha and pixel blend on malidp

Checks the pixel blending mode and plane alpha value when do the plane_check. Mali DP supports blending the current plane with the background either based on the pixel alpha blending mode or by using the layer's alpha value, but not both at the same time. If both case, plane_check will return

[PATCH v5 2/2] drm/mali-dp: Implement plane alpha and pixel blend on malidp

Checks the pixel blending mode and plane alpha value when do the plane_check. Mali DP supports blending the current plane with the background either based on the pixel alpha blending mode or by using the layer's alpha value, but not both at the same time. If both case, plane_check will return