Update file names to match convention

UnleashedRecomp/mutex.h

@@ -0,0 +1,23 @@
+#pragma once
+
+struct Mutex : CRITICAL_SECTION
+{
+    Mutex()
+    {
+        InitializeCriticalSection(this);
+    }
+    ~Mutex()
+    {
+        DeleteCriticalSection(this);
+    }
+
+    void lock()
+    {
+        EnterCriticalSection(this);
+    }
+
+    void unlock()
+    {
+        LeaveCriticalSection(this);
+    }
+};