mu3hook/unity.c: hook Unity plugin DLLs

- Unity loads plugin DLLs and Mono dynamically.

- Ongeki uses Criware for videos so hook the Criware plugin DLL so the
  path hooks load the videos from the hooked paths.

mu3hook/dllmain.c

@@ -11,6 +11,7 @@
 
 #include "mu3hook/config.h"
 #include "mu3hook/io4.h"
+#include "mu3hook/unity.h"
 
 #include "platform/platform.h"
 
@@ -33,6 +34,7 @@ static DWORD CALLBACK mu3_pre_startup(void)
     /* Hook Win32 APIs */
 
     serial_hook_init();
+    unity_hook_init();
 
     /* Initialize emulation hooks */