From: Karsten Keil <kkeil@suse.de>

Solves a endless IRQ loop for Tigerjet 320 based ISDN cards.
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>