This patch updates serial driver for VR41xx serial unit.  Some check are
added to verify_port.
Signed-off-by: Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>