Change important printfs to lg::print (#3355)

This allows them to be logged into a file, useful for debugging.

With this, GOAL `format` and C-kernel `Msg` (and its variants) will be
logged.

game/kernel/common/kmachine.cpp

@@ -229,7 +229,7 @@ void InstallHandler(u32 handler_idx, u32 handler_func) {
       vif1_interrupt_handler = handler_func;
       break;
     default:
-      printf("unknown handler: %d\n", handler_idx);
+      lg::error("unknown handler: {}\n", handler_idx);
       ASSERT(false);
   }
 }