Force the 8230 serial driver to be built in if the on-CPU UARTs are to be
used.  It can't be used as a module because the arch setup needs to call into
it.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>