Cleaned up a few warnings detected by clang

audio_alsa.c

@@ -100,7 +100,7 @@ static void help(void) {
          "    *) default option\n");
 }
 
-int open_mixer() {
+void open_mixer() {
   if (hardware_mixer) {
     debug(2, "Open Mixer");
     int ret = 0;
@@ -463,7 +463,7 @@ int open_alsa_device(void) {
     debug(1,"The alsa buffer is to small (%lu bytes) to accommodate the desired backend buffer length (%ld) you have chosen.",actual_buffer_length,config.audio_backend_buffer_desired_length);
   }
   
-  if ((alsa_characteristics_already_listed==0)) {
+  if (alsa_characteristics_already_listed==0) {
   		alsa_characteristics_already_listed=1;
   		
   		int rc;

mdns_avahi.c

@@ -38,6 +38,7 @@
 #include <avahi-common/error.h>
 
 #include <avahi-client/lookup.h>
+#include <avahi-common/alternative.h>
 
 static AvahiServiceBrowser *sb = NULL;
 static AvahiClient *client = NULL;
@@ -171,8 +172,8 @@ static void egroup_callback(AvahiEntryGroup *g, AvahiEntryGroupState state,
 
          /* A service name collision with a remote service
           * happened. Let's pick a new name */
-         n = avahi_alternative_service_name( name );
-         avahi_free( name );
+         n = avahi_alternative_service_name(name);
+         avahi_free(name);
          name = n;
 
          debug(2,"avahi: service name collision, renaming service to '%s'", name );