Minor warning fixes when running under FreeBSD

src/Pty.cpp

@@ -148,6 +148,8 @@ void Pty::setUtf8Mode(bool enable)
         if (!pty()->tcSetAttr(&ttmode))
             kWarning() << "Unable to set terminal attributes.";
     }
+#else
+    Q_UNUSED(enable);
 #endif
 }