Use menuconfig objects: ISDN/Gigaset

Change Kconfig objects from "menu, config" into "menuconfig" so that the user
can disable the whole feature without having to enter the menu first.
Signed-off-by: Jan Engelhardt <jengelh@gmx.de>
Cc: Tilman Schmidt <tilman@imap.cc>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/isdn/gigaset/Kconfig

-menu "Siemens Gigaset"
-
-config ISDN_DRV_GIGASET
+menuconfig ISDN_DRV_GIGASET
 	tristate "Siemens Gigaset support (isdn)"
 	select CRC_CCITT
 	select BITREVERSE
@@ -53,6 +51,4 @@ config GIGASET_UNDOCREQ
 	  features like configuration mode of M105, say yes. If you
 	  care about your device, say no.
 
-endif
-
-endmenu
+endif # ISDN_DRV_GIGASET != n