NFC: nfcmrvl: Auto-select core module

As I understand it, the core nfcmrvl module is useless without
either the USB or the UART access module. So hide NFC_MRVL and select
it automatically if either NFC_MRVL_USB or NFC_MRVL_UART is selected.

This avoids presenting NFC_MRVL when neither NFC_MRVL_USB nor
NFC_MRVL_UART can be selected.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Lauro Ramos Venancio <lauro.venancio@openbossa.org>
Cc: Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/nfc/nfcmrvl/Kconfig

 config NFC_MRVL
-	tristate "Marvell NFC driver support"
-	depends on NFC_NCI
+	tristate
 	help
 	  The core driver to support Marvell NFC devices.
 
 	  This driver is required if you want to support
 	  Marvell NFC device 8897.
 
-	  Say Y here to compile Marvell NFC driver into the kernel or
-	  say M to compile it as module.
-
 config NFC_MRVL_USB
 	tristate "Marvell NFC-over-USB driver"
-	depends on NFC_MRVL && USB
+	depends on NFC_NCI && USB
+	select NFC_MRVL
 	help
 	  Marvell NFC-over-USB driver.
 
@@ -24,7 +21,8 @@ config NFC_MRVL_USB
 
 config NFC_MRVL_UART
 	tristate "Marvell NFC-over-UART driver"
-	depends on NFC_MRVL && NFC_NCI_UART
+	depends on NFC_NCI && NFC_NCI_UART
+	select NFC_MRVL
 	help
 	  Marvell NFC-over-UART driver.