Import libultraship as a submodule (#1943)

Co-authored-by: briaguya <briaguya>
Co-authored-by: Christopher Leggett <chris@leggett.dev>
Co-authored-by: David Chavez <davi@dcvz.io>

soh/soh/Enhancements/randomizer/randomizer_check_objects.cpp

@@ -1,7 +1,7 @@
 #include "randomizer_check_objects.h"
 #include <map>
 #include <string>
-#include <libultraship/Cvar.h>
+#include <Cvar.h>
 #include "z64.h"
 
 /*