SDL: wikiheaders: Maybe fix perl warning.

SDL Commits
1

https://github.com/libsdl-org/SDL/commit/2b8fb0bdd471317309a9bfc0d2917ef54dcdaa6e

From 2b8fb0bdd471317309a9bfc0d2917ef54dcdaa6e Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Mon, 13 Jan 2025 15:17:52 -0500
Subject: [PATCH] wikiheaders: Maybe fix perl warning.

Reference Issue #11944.
---
 build-scripts/wikiheaders.pl | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/build-scripts/wikiheaders.pl b/build-scripts/wikiheaders.pl
index 554b9903651e0..98591493b7cc5 100755
--- a/build-scripts/wikiheaders.pl
+++ b/build-scripts/wikiheaders.pl
@@ -2792,7 +2792,8 @@ sub generate_quickref {
         my $decl = $headerdecls{$sym};
         my $str = '';
 
-        $brief = "$brief";
+        # the "$brief" makes sure this is a copy of the string, which is doing some weird reference thing otherwise.
+        $brief = defined $brief ? "$brief" : '';
         $brief =~ s/\A[\s\n]*\= .*? \=\s*?\n+//ms;
         $brief =~ s/\A[\s\n]*\=\= .*? \=\=\s*?\n+//ms;
         $brief =~ s/\A(.*?\.) /$1\n/;  # \brief should only be one sentence, delimited by a period+space. Split if necessary.