output/raop: consistently use GError

src/mixer/raop_mixer_plugin.c

@@ -63,11 +63,11 @@ raop_mixer_get_volume(struct mixer *mixer, G_GNUC_UNUSED GError **error_r)
 }
 
 static bool
-raop_mixer_set_volume(struct mixer *mixer, unsigned volume, G_GNUC_UNUSED GError **error_r)
+raop_mixer_set_volume(struct mixer *mixer, unsigned volume, GError **error_r)
 {
 	struct raop_mixer_plugin *rm = (struct raop_mixer_plugin *)mixer;
 	g_debug("raop_mixer_set_volume\n");
-	return raop_set_volume(rm->rd, volume);
+	return raop_set_volume(rm->rd, volume, error_r);
 }
 
 const struct mixer_plugin raop_mixer_plugin = {

src/output/raop_output_plugin.h

@@ -155,7 +155,7 @@ struct raop_session_data {
 /*********************************************************************/
 
 bool
-raop_set_volume(struct raop_data *rd, unsigned volume);
+raop_set_volume(struct raop_data *rd, unsigned volume, GError **error_r);
 
 int
 raop_get_volume(struct raop_data *rd);

test/read_mixer.c

@@ -60,7 +60,8 @@ pulse_output_set_volume(G_GNUC_UNUSED struct pulse_output *po,
 
 bool
 raop_set_volume(G_GNUC_UNUSED struct raop_data *rd,
-		G_GNUC_UNUSED unsigned volume)
+		G_GNUC_UNUSED unsigned volume,
+		G_GNUC_UNUSED GError **error_r)
 {
 	return false;
 }