wayland: don't use libdecor_frame_get_* functions when header doesn't have it

and we're statically linking to the library.
This fixes building SDL with -DSDL_WAYLAND_SHARED=OFF

src/video/wayland/SDL_waylandsym.h

@@ -218,6 +218,7 @@ SDL_WAYLAND_SYM(bool, libdecor_configuration_get_window_state, (struct libdecor_
                                                                 enum libdecor_window_state *))
 SDL_WAYLAND_SYM(int, libdecor_dispatch, (struct libdecor *, int))
 
+#if defined(SDL_VIDEO_DRIVER_WAYLAND_DYNAMIC_LIBDECOR) || defined(SDL_HAVE_LIBDECOR_GET_MIN_MAX)
 /* Only found in libdecor 0.1.1 or higher, so failure to load them is not fatal. */
 SDL_WAYLAND_SYM_OPT(void, libdecor_frame_get_min_content_size, (struct libdecor_frame *,\
                                                             int *,\
@@ -227,6 +228,8 @@ SDL_WAYLAND_SYM_OPT(void, libdecor_frame_get_max_content_size, (struct libdecor_
                                                             int *))
 #endif
 
+#endif
+
 #undef SDL_WAYLAND_MODULE
 #undef SDL_WAYLAND_SYM
 #undef SDL_WAYLAND_SYM_OPT