Vendor raptor source files (was embedded gitlink)

Tree vendored at upstream 0019c5dd; origin + license recorded in
raptor/VENDOR.txt. Windows SDL dev packages excluded via .gitignore.

raptor/src/musapi.h

@@ -0,0 +1,29 @@
+#pragma once
+#include <stdint.h>
+#include "common.h"
+
+struct musdevice_t {
+    int (*Init)(int option);
+    void (*DeInit)(void);
+    void (*Mix)(int16_t *stream, int len);
+    
+    void (*KeyOffEvent)(unsigned int chan, unsigned int key);
+    void (*KeyOnEvent)(int chan, unsigned int key, unsigned int volume);
+    void (*ControllerEvent)(unsigned int chan, unsigned int controller, unsigned int param);
+    void (*PitchBendEvent)(unsigned int chan, int bend);
+    void (*ProgramEvent)(unsigned int chan, unsigned int param);
+    void (*AllNotesOffEvent)(unsigned int chan, unsigned int param);
+};
+
+extern musdevice_t mus_device_opl, mus_device_winmm, mus_device_tsf, mus_device_alsa, mus_device_corea, mus_device_corem;
+extern musdevice_t *music_device;
+
+
+int MUS_Init(int card, int option);
+void MUS_DeInit(void);
+void MUS_PlaySong(void *ptr, int loop, int fadein);
+void MUS_StopSong(int fadeout);
+int MUS_SongPlaying(void);
+void MUS_Mix(int16_t *stream, int len);
+void MUS_Poll(void);
+void MUS_SetVolume(int volume);