[PATCH] ipmi: fix a deadlock

Correct an issue with the IPMI message layer taking a lock and calling
lower layer driver.  If an error occrues at the lower layer the lock can be
taken again causing a deadlock.  The lock is released before calling the
lower layer.

Signed-off-by: David Griego <dgriego@mvista.com>
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>