drivers/isdn: Add module.h to ISDN files implicitly using it.

So that we don't get build failures once the implicit module.h
presence is terminated.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

drivers/isdn/gigaset/interface.c

@@ -14,6 +14,7 @@
 #include "gigaset.h"
 #include <linux/gigaset_dev.h>
 #include <linux/tty_flip.h>
+#include <linux/module.h>
 
 /*** our ioctls ***/
 

drivers/isdn/hardware/mISDN/mISDNisar.c

@@ -29,6 +29,7 @@
 #include <linux/delay.h>
 #include <linux/vmalloc.h>
 #include <linux/mISDNhw.h>
+#include <linux/module.h>
 #include "isar.h"
 
 #define ISAR_REV	"2.1"

drivers/isdn/i4l/isdn_tty.c

@@ -750,6 +750,7 @@ isdn_tty_modem_hup(modem_info * info, int local)
  * supplementary service (CAPI 2.0 part III)
  */
 #include <linux/isdn/capicmd.h>
+#include <linux/module.h>
 
 int
 isdn_tty_capi_facility(capi_msg *cm) {