Only remove motd instructions once

src/freedombone-utils-setup

@@ -379,7 +379,9 @@ function mark_admin_user_account {
 }
 
 function remove_instructions_from_motd {
-    sed -i '/## /d' /etc/motd
+    if grep -q "## " /etc/motd; then
+        sed -i '/## /d' /etc/motd
+    fi
 }
 
 function remove_default_user {