mdmngr: set library debugging level to whatever the mdmngr debugging level is

mdmngr.c

@@ -151,6 +151,7 @@ static int parse_args(int argc, char **argv)
 				printf("%s: option '-%c' is invalid.\n", argv[0], optopt);
 				goto fail;
 			}
+			set_lib_debug(debug);
 			break;
 		case ':':
 			fprintf(stderr, "%s: option '-%c' requires an argument\n", argv[0], optopt);