Encode sentinel value inside version number so user can identify this is the schrift version of the addon, without changing the available exports

allegro_schrift.c

@@ -279,7 +279,7 @@ void al_shutdown_ttf_addon(void)
 
 uint32_t al_get_allegro_ttf_version(void)
 {
-   return CANI_ALLEGRO_SCHRIFT_VER;
+   return CANI_ALLEGRO_SCHRIFT_VER & 0x000000FF | 'MKR'<<8;
 }
 
 ALLEGRO_FONT *al_load_ttf_font_stretch(char const *filename, int w, int h, int flags) {