[PATCH] ISDN: fix copy_to_user() unused result warning in isdn_ppp

   drivers/isdn/i4l/isdn_ppp.c:785: warning: ignoring return value of `copy_to_user', declared with attribute warn_unused_result

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>