arch/sh: Implement <asm/fb.h> with generic helpers

Replace the architecture's fbdev helpers with the generic
ones from <asm-generic/fb.h>. No functional changes.

v2:
* use default implementation for fb_pgprotect() (Arnd)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Acked-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230417125651.25126-17-tzimmermann@suse.de

sh: include: convert to SPDX identifiers

Update license to use SPDX-License-Identifier instead of verbose license
text.

Link: http://lkml.kernel.org/r/87ftvccszx.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

sh: migrate to arch/sh/include/

This follows the sparc changes a439fe51a1f8eb087c22dd24d69cebae4a3addac.

Most of the moving about was done with Sam's directions at:

http://marc.info/?l=linux-sh&m=121724823706062&w=2

with subsequent hacking and fixups entirely my fault.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>