add extra functions to paddles

This theoretically should enable the Home and Disconnect buttons on the Steam Deck, even though we should still have comprehensive remapping functionality for completeness

Author: itsmattkc

rpi/ui/ui_sdl.c

@@ -76,6 +76,10 @@ void init_gamepad()
     button_map[SDL_CONTROLLER_BUTTON_DPAD_DOWN] = VANILLA_BTN_DOWN;
     button_map[SDL_CONTROLLER_BUTTON_DPAD_LEFT] = VANILLA_BTN_LEFT;
     button_map[SDL_CONTROLLER_BUTTON_DPAD_RIGHT] = VANILLA_BTN_RIGHT;
+    button_map[SDL_CONTROLLER_BUTTON_PADDLE1] = VANILLA_BTN_HOME;
+    button_map[SDL_CONTROLLER_BUTTON_PADDLE2] = VPI_ACTION_DISCONNECT;
+    button_map[SDL_CONTROLLER_BUTTON_PADDLE3] = VPI_ACTION_SCREENSHOT;
+    button_map[SDL_CONTROLLER_BUTTON_PADDLE4] = VPI_ACTION_TOGGLE_RECORDING;
     axis_map[SDL_CONTROLLER_AXIS_LEFTX] = VANILLA_AXIS_L_X;
     axis_map[SDL_CONTROLLER_AXIS_LEFTY] = VANILLA_AXIS_L_Y;
     axis_map[SDL_CONTROLLER_AXIS_RIGHTX] = VANILLA_AXIS_R_X;