USB: cdc-acm.c: Fix compile warnings

The irq flags should be unsigned long.

  CC [M]  drivers/usb/class/cdc-acm.o
drivers/usb/class/cdc-acm.c: In function 'acm_waker':
drivers/usb/class/cdc-acm.c:527: warning: comparison of distinct pointer types lacks a cast
drivers/usb/class/cdc-acm.c:529: warning: comparison of distinct pointer types lacks a cast

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>