sgi-xp/sgi-gru: allow modules to load on non-uv systems

For an upcoming distro release, we need to have the xp kernel module
loadable even when not on UV equipment.  The xpc module will not load.
This will allow one set of modules dependent upon xp to work on either UV
or non-UV equipment.

Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>