drm: renesas: shmobile: Fix ARGB32 overlay format typo
When configuring a CHn Source Image Format Register (LDBBSIFR), one
should use the corresponding LDBBSIFR_RPKF_* definition for overlay
planes, not the DDFR_PKF_* definition for the primary plane.
Fortunately both definitions resolve to the same value, so this bug did
not cause any harm.
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/34f8d51539c048e264699ca869ad9d7a952cd69f.1694767209.git.geert+renesas@glider.be