wayland: Fix variable scope

src/video/wayland/SDL_waylandevents.c

@@ -1428,6 +1428,7 @@ static size_t xkb_legacy_get_mods_for_level(SDL_WaylandSeat *seat, xkb_keycode_t
         return 1;
     }
 
+    size_t mask_idx = 0;
     struct xkb_state *state = WAYLAND_xkb_state_new(seat->keyboard.xkb.keymap);
     if (state) {
         const xkb_mod_mask_t keymod_masks[] = {
@@ -1447,8 +1448,6 @@ static size_t xkb_legacy_get_mods_for_level(SDL_WaylandSeat *seat, xkb_keycode_t
         const xkb_mod_mask_t pressed_mod_mask = seat->keyboard.xkb.shift_mask | seat->keyboard.xkb.level3_mask | seat->keyboard.xkb.level5_mask;
         const xkb_mod_mask_t locked_mod_mask = seat->keyboard.xkb.caps_mask;
 
-        size_t mask_idx = 0;
-
         for (size_t i = 0; i < SDL_arraysize(keymod_masks); ++i) {
             WAYLAND_xkb_state_update_mask(state, keymod_masks[i] & pressed_mod_mask, 0, keymod_masks[i] & locked_mod_mask, 0, 0, layout);
             if (WAYLAND_xkb_state_key_get_level(state, key, layout) == level) {