Add box mode to disable stick commands

Adds a `STICK COMMAND DISABLE SW` mode used to prevent inadvertant triggering of controls, calibrations, or settings changes. Useful for USB HID mode when using the flight controller as a joystick (and auto-detect doesn't work), in "team" or "relay" racing where multiple quads might be bound to the same transmitter, or just in general if the user wants prevent stick commands.

Will also prevent stick arming when the mode is active (but not stick disarming).

src/main/fc/rc_modes.h

@@ -75,6 +75,7 @@ typedef enum {
     BOXVTXCONTROLDISABLE,
     BOXLAUNCHCONTROL,
     BOXMSPOVERRIDE,
+    BOXSTICKCOMMANDDISABLE,
     CHECKBOX_ITEM_COUNT
 } boxId_e;