winepulse: Export get_device_guid().

dlls/winepulse.drv/mmdevdrv.c

@@ -103,7 +103,7 @@ static void pulse_call(enum unix_funcs code, void *params)
     assert(!status);
 }
 
-static void get_device_guid(EDataFlow flow, const char *pulse_name, GUID *guid)
+void WINAPI get_device_guid(EDataFlow flow, const char *pulse_name, GUID *guid)
 {
     WCHAR key_name[MAX_PULSE_NAME_LEN + 2];
     DWORD type, size = sizeof(*guid);

dlls/winepulse.drv/winepulse.drv.spec

 # MMDevAPI driver functions
+@ stdcall -private get_device_guid(long ptr ptr) get_device_guid
 @ stdcall -private get_device_name_from_guid(ptr ptr ptr) get_device_name_from_guid
 @ stdcall -private GetEndpointIDs(long ptr ptr ptr ptr) AUDDRV_GetEndpointIDs