nntp: remove unused header_append method

It was unused since 1bf653ad139bf7bb3d853ab0b5eae3eaa1b13a95
("nntp+www: drop List-* and Archived-At headers")

diff --git a/lib/PublicInbox/NNTP.pm b/lib/PublicInbox/NNTP.pm
index 18822d3b014a097482718e29b4f627c2286f9478..f7d99913d350e314dcedc9c79b3989d46f9ff29f 100644 (file)
--- a/lib/PublicInbox/NNTP.pm
+++ b/lib/PublicInbox/NNTP.pm
@@ -409,15 +409,6 @@ sub cmd_quit ($) {
        undef;
 }
 
-sub header_append ($$$) {
-       my ($hdr, $k, $v) = @_;
-       my @v = $hdr->header_raw($k);
-       foreach (@v) {
-               return if $v eq $_;
-       }
-       $hdr->header_set($k, @v, $v);
-}
-
 sub xref_by_tc ($$$) {
        my ($xref, $pi_cfg, $smsg) = @_;
        my $by_addr = $pi_cfg->{-by_addr};