Staging: VME: PIO2: Add GPIOLIB dependancy

The PIO2 driver errors when GPIOLIB, on which it depends, is not enabled.

Add dependancy when selecting the PIO2.
Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Martyn Welch <martyn.welch@ge.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/vme/devices/Kconfig

@@ -9,6 +9,7 @@ config VME_USER
 
 config VME_PIO2
 	tristate "GE PIO2 VME"
+	depends on GPIOLIB
 	help
 	  Say Y here to include support for the GE PIO2. The PIO2 is a 6U VME
 	  slave card, implementing 32 solid-state relay switched IO lines, in