SDL: SDL_utf8strlen: run bit-test explicitly on unsigned char

From 507d4bcd68599a23097132f82dfdd9e4ede8a154 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Sat, 18 Dec 2021 14:01:02 +0300
Subject: [PATCH] SDL_utf8strlen: run bit-test explicitly on unsigned char

---
 src/stdlib/SDL_string.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/stdlib/SDL_string.c b/src/stdlib/SDL_string.c
index 13d6c542efc..7a894ded459 100644
--- a/src/stdlib/SDL_string.c
+++ b/src/stdlib/SDL_string.c
@@ -670,7 +670,7 @@ SDL_utf8strlen(const char *str)
 {
     size_t retval = 0;
     const char *p = str;
-    char ch;
+    unsigned char ch;
 
     while ((ch = *(p++)) != 0) {
         /* if top two bits are 1 and 0, it's a continuation byte. */