SDL: wikiheaders: Fix uninitialized variable issue.

SDL Commits
1 
From 9a9616894d5d2d517bca5577d572fef5123a1441 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Fri, 13 Dec 2024 13:52:35 -0500
Subject: [PATCH] wikiheaders: Fix uninitialized variable issue.

---
 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 970e9dfd41c8c..6a0532043dd93 100755
--- a/build-scripts/wikiheaders.pl
+++ b/build-scripts/wikiheaders.pl
@@ -956,7 +956,8 @@ sub generate_quickref {
             if (defined $brief) {
                 $brief = "$brief";
                 chomp($brief);
-                $brief = dewikify($wikitypes{$sym}, $brief);
+                my $thiswikitype = defined $wikitypes{$sym} ? $wikitypes{$sym} : 'md';  # default to MarkDown for new stuff.
+                $brief = dewikify($thiswikitype, $brief);
                 my $spaces = ' ' x ($maxlen - length($csig));
                 $brief = "$spaces// $brief";
             } else {