media: media: sh_veu: Remove driver

Since its inclusion in v3.9, no users of the SuperH VEU mem2mem video
processing driver have appeared upstream.  All VEU devices in SuperH
board code still bind to the "uio_pdrv_genirq" driver instead.
The original author marked the driver orphaned in v3.15.

Remove the driver; it can always be resurrected from git history when
needed.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Landley <rob@landley.net>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>