reserve: update from upstream git repo

src/modules/reserve.h

@@ -1,3 +1,5 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: t -*-*/
+
 #ifndef fooreservehfoo
 #define fooreservehfoo
 
@@ -28,6 +30,10 @@
 #include <dbus/dbus.h>
 #include <inttypes.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct rd_device rd_device;
 
 /* Prototype for a function that is called whenever someone else wants
@@ -66,4 +72,8 @@ void rd_set_userdata(rd_device *d, void *userdata);
  * userdata was set. */
 void* rd_get_userdata(rd_device *d);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif