usb: gadget: legacy: nokia: add CONFIG_BLOCK dependency

g_nokia now has mass_storage function, so it should
depend on CONFIG_BLOCK.
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/legacy/Kconfig

@@ -339,6 +339,7 @@ config USB_CDC_COMPOSITE
 config USB_G_NOKIA
 	tristate "Nokia composite gadget"
 	depends on PHONET
+	depends on BLOCK
 	select USB_LIBCOMPOSITE
 	select USB_U_SERIAL
 	select USB_U_ETHER