SDL: wikiheaders.pl: Add --copy-to-header option.

SDL Commits
1 
From c07e5e99c889e9f5fc39c36dcfee2fbaedb85766 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Wed, 14 Jul 2021 17:07:41 -0400
Subject: [PATCH] wikiheaders.pl: Add --copy-to-header option.

...because I keep mistyping it without the 's' on the end.  :/
---
 build-scripts/wikiheaders.pl | 1 +
 1 file changed, 1 insertion(+)

diff --git a/build-scripts/wikiheaders.pl b/build-scripts/wikiheaders.pl
index f33216138..d00631c7d 100755
--- a/build-scripts/wikiheaders.pl
+++ b/build-scripts/wikiheaders.pl
@@ -12,6 +12,7 @@
 foreach (@ARGV) {
     $warn_about_missing = 1, next if $_ eq '--warn-about-missing';
     $copy_direction = 1, next if $_ eq '--copy-to-headers';
+    $copy_direction = 1, next if $_ eq '--copy-to-header';
     $copy_direction = -1, next if $_ eq '--copy-to-wiki';
     $srcpath = $_, next if not defined $srcpath;
     $wikipath = $_, next if not defined $wikipath;