Revert "dss/dispc: add BGRA32 to color_mode_to_bpp"

This reverts commit 27fb52c31277ecc98dda366cf31abef42db6e76e.
Revert "dss_feature: add BGRA8888 format to allowed modes"

This reverts commit 28fa5a6c931e68379a73580305da1dab342d9b15.