video/logo: Remove MIPS-specific include section

Since commit 41702d9a ("logo.c: get rid of
mips_machgroup") there's no longer a need to include <asm/bootinfo.h> on
MIPS.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>