Added HIDAPI backend for Amazon Luna Controller Model T28B69 connected via Bluetooth LE (VID:0171, PID:0419).

To enter Bluetooth pairing mode hold B and Action (button with circle) buttons for 3 seconds.

It works via usual HIDAPI if special filter driver is not installed:
https://www.amazon.com/gp/help/customer/display.html?nodeId=GZCT4CTFHXLHEB9T

With that driver installed it mimics Xbox One controller and works via XInput under Windows.

Under DInput this controller is not usable at all.

include/SDL_gamecontroller.h

@@ -619,7 +619,7 @@ typedef enum
     SDL_CONTROLLER_BUTTON_DPAD_DOWN,
     SDL_CONTROLLER_BUTTON_DPAD_LEFT,
     SDL_CONTROLLER_BUTTON_DPAD_RIGHT,
-    SDL_CONTROLLER_BUTTON_MISC1,    /* Xbox Series X share button, PS5 microphone button, Nintendo Switch Pro capture button */
+    SDL_CONTROLLER_BUTTON_MISC1,    /* Xbox Series X share button, PS5 microphone button, Nintendo Switch Pro capture button, Amazon Luna microphone button */
     SDL_CONTROLLER_BUTTON_PADDLE1,  /* Xbox Elite paddle P1 */
     SDL_CONTROLLER_BUTTON_PADDLE2,  /* Xbox Elite paddle P3 */
     SDL_CONTROLLER_BUTTON_PADDLE3,  /* Xbox Elite paddle P2 */

include/SDL_hints.h

@@ -751,6 +751,17 @@ extern "C" {
  */
 #define SDL_HINT_JOYSTICK_HIDAPI_GAMECUBE "SDL_JOYSTICK_HIDAPI_GAMECUBE"
 
+ /**
+  *  \brief  A variable controlling whether the HIDAPI driver for Amazon Luna controllers connected via Bluetooth should be used.
+  *
+  *  This variable can be set to the following values:
+  *    "0"       - HIDAPI driver is not used
+  *    "1"       - HIDAPI driver is used
+  *
+  *  The default is the value of SDL_HINT_JOYSTICK_HIDAPI
+  */
+#define SDL_HINT_JOYSTICK_HIDAPI_LUNA "SDL_JOYSTICK_HIDAPI_LUNA"
+
 /**
  *  \brief  A variable that controls whether Steam Controllers should be exposed using the SDL joystick and game controller APIs
  *