SDL: Applied DragonFly BSD patch (7f42f)

SDL Commits
1 
From 7f42fb54adbb9fa86bbdbd09abac628ccfaef648 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Sat, 30 Jul 2022 16:34:40 -0700
Subject: [PATCH] Applied DragonFly BSD patch

https://github.com/DragonFlyBSD/DeltaPorts/blob/master/ports/devel/sdl20/dragonfly/patch-src_stdlib_SDL__malloc.c
---
 src/stdlib/SDL_malloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/stdlib/SDL_malloc.c b/src/stdlib/SDL_malloc.c
index 980120bc40f..1e986f6152e 100644
--- a/src/stdlib/SDL_malloc.c
+++ b/src/stdlib/SDL_malloc.c
@@ -1249,7 +1249,7 @@ extern "C"
 #ifndef LACKS_UNISTD_H
 #include <unistd.h>             /* for sbrk */
 #else /* LACKS_UNISTD_H */
-#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
+#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__) && !defined(__DragonFly__)
 extern void *sbrk(ptrdiff_t);
 #endif /* FreeBSD etc */
 #endif /* LACKS_UNISTD_H */