script: multiap: handle spaces when re-writing WSC metadata to 1905 config

src/script/multiap

@@ -141,7 +141,7 @@ sync_credentials() {
 					shift
 					continue
 				}
-				json_add_string "$key" ${val}
+				json_add_string "$key" "${val}"
 				key=$1
 				shift
 			done