osxaudio: break as soon as the device is found

No need to loop further if there's no side-effects for it
diff --git a/sys/osxaudio/gstosxcoreaudiohal.c b/sys/osxaudio/gstosxcoreaudiohal.c
index 36bd85e..4505c29 100644
--- a/sys/osxaudio/gstosxcoreaudiohal.c
+++ b/sys/osxaudio/gstosxcoreaudiohal.c
@@ -1245,6 +1245,7 @@
     for (i = 0; i < ndevices; i++) {
       if (device_id == devices[i]) {
         res = TRUE;
+        break;
       }
     }