Fixed build.

src/bgfx.cpp

@@ -226,7 +226,7 @@ namespace bgfx
 
 	protected:
 #if BGFX_CONFIG_MEMORY_TRACKING
-		bx::LwMutex m_mutex;
+		bx::Mutex m_mutex;
 		uint32_t m_numBlocks;
 		uint32_t m_maxBlocks;
 #endif // BGFX_CONFIG_MEMORY_TRACKING