ipfw: line up ipfw -t list with and without timestamp

From the PR:
    When I run `ipfw -t list` on release/12 or current, I get misaligned
    output between lines that do and do not have a last match timestamp,
    like so:

    00100 Tue Aug 11 03:03:26 2020 allow ip from any to any via lo0
    00200                         deny ip from any to 127.0.0.0/8

    (specifically, the "allow" and "deny" strings do not line up)

PR:		248608
Submitted by:	Taylor Stearns
MFC after:	3 days

sbin/ipfw/ipfw2.c

@@ -2199,7 +2199,7 @@ show_static_rule(struct cmdline_opts *co, struct format_opts *fo,
 			*strchr(timestr, '\n') = '\0';
 			bprintf(bp, "%s ", timestr);
 		} else {
-			bprintf(bp, "%*s", twidth, " ");
+			bprintf(bp, "%*s", twidth + 1, " ");
 		}
 	}