Surprise! Added support for microphone emulation, but only for Win32.

There are 3 problems : 
1. the sound crackles a bit
2. the microphone amplifier isn't supported
3. the emu freezes if you don't close it by the console

desmume/src/mic.h

@@ -0,0 +1,21 @@
+#ifndef MIC_H
+#define MIC_H
+
+#ifdef WIN32
+
+BOOL Mic_Init();
+void Mic_Reset();
+void Mic_DeInit();
+u8 Mic_ReadSample();
+
+#else
+/* TODO : mic support for other platforms */
+
+BOOL Mic_Init() { return TRUE; }
+void Mic_Reset() { }
+void Mic_DeInit() { }
+u8 Mic_ReadSample() { return 0; }
+
+#endif
+
+#endif