FPSCounter: Initialize members.

Source/Core/VideoCommon/FPSCounter.cpp

@@ -13,6 +13,9 @@
 #define FPS_REFRESH_INTERVAL 1000
 
 FPSCounter::FPSCounter()
+	: m_fps(0)
+	, m_counter(0)
+	, m_fps_last_counter(0)
 {
 	m_update_time.Update();
 	m_render_time.Update();