Error found by Jeff Haran.

The error detect register is 0s when no errors are detected.  The check
code is incorrect, so reverse check sense.
Reported-by: Jeff Haran <jharan@Brocade.COM>
Signed-off-by: Dave Jiang <djiang@mvista.com>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>