Move mutex and mem create/cleanup functions into mutex.c and mem.c respectively

kernel/proc/mutex.h

@@ -15,6 +15,8 @@ struct proc_mutex {
   struct proc* owner;
 };
 
+bool proc_create_resource_mutex (struct proc_mutex* mutex);
+void proc_cleanup_resource_mutex (struct proc* proc, struct proc_resource* resource);
 void proc_mutex_lock (struct proc* proc, struct proc_mutex* mutex);
 bool proc_mutex_unlock (struct proc* proc, struct proc_mutex* mutex);