Make USB HID/PID force feedback an experimental option.

drivers/usb/input/Config.in

@@ -9,7 +9,7 @@ if [ "$CONFIG_INPUT" = "n" ]; then
 fi
 
 dep_mbool '    HID input layer support' CONFIG_USB_HIDINPUT $CONFIG_INPUT $CONFIG_USB_HID
-dep_mbool '      Force feedback support' CONFIG_HID_FF $CONFIG_USB_HIDINPUT
+dep_mbool '      Force feedback support (EXPERIMENTAL)' CONFIG_HID_FF $CONFIG_USB_HIDINPUT $CONFIG_EXPERIMENTAL
 dep_mbool '        PID Devices' CONFIG_HID_PID $CONFIG_USB_HID $CONFIG_HID_FF
 dep_mbool '        Logitech RumblePad support' CONFIG_LOGITECH_RUMBLE $CONFIG_USB_HID $CONFIG_HID_FF
 dep_mbool '        Logitech WingMan Force 3D support' CONFIG_LOGITECH_3D $CONFIG_USB_HID $CONFIG_HID_FF