SDL: Make sure we include the null terminator in XLookupStringAsUTF8() (70ada)

SDL Commits
1 
From 70adacf08aaead025a58f005a1a183cce76bc726 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Tue, 7 Nov 2023 16:24:08 -0800
Subject: [PATCH] Make sure we include the null terminator in
 XLookupStringAsUTF8()

Fixes https://github.com/libsdl-org/SDL/issues/6728

(cherry picked from commit 4106697774ff533b2eeb223f87103fa464fc598a)
---
 src/video/x11/SDL_x11events.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/video/x11/SDL_x11events.c b/src/video/x11/SDL_x11events.c
index 55d151e63c45..08cede4e2e43 100644
--- a/src/video/x11/SDL_x11events.c
+++ b/src/video/x11/SDL_x11events.c
@@ -756,7 +756,7 @@ static int XLookupStringAsUTF8(XKeyEvent *event_struct, char *buffer_return, int
 {
     int result = X11_XLookupString(event_struct, buffer_return, bytes_buffer, keysym_return, status_in_out);
     if (IsHighLatin1(buffer_return, result)) {
-        char *utf8_text = SDL_iconv_string("UTF-8", "ISO-8859-1", buffer_return, result);
+        char *utf8_text = SDL_iconv_string("UTF-8", "ISO-8859-1", buffer_return, result + 1);
         if (utf8_text) {
             SDL_strlcpy(buffer_return, utf8_text, bytes_buffer);
             SDL_free(utf8_text);