[PATCH] txx9 serial update

Support for the new RBHMA4500 eval board for the TX4938.  General update
from the 8250 ancestor of this driver.  Replace use of deprecated
interfaces.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>