Removed SDL_IPHONE_MAX_GFORCE

We no longer support interpreting the accelerometer as a joystick.

Fixes https://github.com/libsdl-org/SDL/issues/11005

include/SDL3/SDL_joystick.h

@@ -161,12 +161,6 @@ typedef enum SDL_JoystickConnectionState
 #define SDL_JOYSTICK_AXIS_MIN   -32768
 
 
-/* Set max recognized G-force from accelerometer
-   See src/joystick/uikit/SDL_sysjoystick.m for notes on why this is needed
- */
-#define SDL_IPHONE_MAX_GFORCE 5.0
-
-
 /* Function prototypes */
 
 /**