arm_interface: Replace kernel vm_manager include with a forward declaration

Avoids an unnecessary inclusion and also uncovers three places where
indirect inclusions were relied upon, which allows us to also resolve
those.

src/core/hle/kernel/mutex.cpp

@@ -16,6 +16,7 @@
 #include "core/hle/kernel/object.h"
 #include "core/hle/kernel/thread.h"
 #include "core/hle/result.h"
+#include "core/memory.h"
 
 namespace Kernel {