Some spinlock changes were introduced in 1.9.1 original moxa driver.  Revert
them, since they cause machine not responding.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>