[PATCH] mwave: interesting flags savings

Flags from spin_lock_irqsave() are saved into global variable and restored
from it.  My gut feeling this is very racy.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>