logo.c: get rid of mips_machgroup

This has not been any serious user of this ill conceived thing since the
original invention in like '95 so I recently deleted this from everywhere
except the last instance in logo.c.  This patch removes the last two
instances in logo.c.  They conditions were not useful anyway as when
compiled in they would always evaluate as true.

Last not least this is necessary to get the SGI IP22 and DECstation kernels
to compile again.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>