fix copy pasta error

shared

@@ -13,7 +13,8 @@ if [ -z "${password}" ]; then
 	echo "WARNING: password in ${config} is missing!" >&2
 fi
 
+# get tresor config value in a safe way
 tresor="$(grep tresor ${basedir}/${config} 2>/dev/null|cut -d= -f2|tr -d ' \t')"
-if [ -z "${password}" ]; then
+if [ -z "${tresor}" ]; then
 	echo "WARNING: tresor in ${config} is missing!" >&2
 fi