[PATCH] Fix typo in drivers/isdn/hisax/q931.c

This fixes coverity bug #517.

Since IESIZE is greater than IESIZE_NI1 we might run past the end of
ielist_ni1.  This fixes it by using the proper IESIZE_NI1 define.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>