SDL: Allow defining custom SDL_SINT64_C and SDL_UINT64_C macros (#11315)

SDL Commits
1 
From d0cf2c19d1a3aa59b50198634da6854ef597de88 Mon Sep 17 00:00:00 2001
From: Susko3 <[EMAIL REDACTED]>
Date: Thu, 24 Oct 2024 01:03:13 +0100
Subject: [PATCH] Allow defining custom SDL_SINT64_C and SDL_UINT64_C macros
 (#11315)

---
 include/SDL3/SDL_stdinc.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/SDL3/SDL_stdinc.h b/include/SDL3/SDL_stdinc.h
index 462ce4b20795e..71c4073b96758 100644
--- a/include/SDL3/SDL_stdinc.h
+++ b/include/SDL3/SDL_stdinc.h
@@ -256,6 +256,8 @@ void *alloca(size_t);
      (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (C))) << 16) | \
      (SDL_static_cast(Uint32, SDL_static_cast(Uint8, (D))) << 24))
 
+#if !(defined(SDL_SINT64_C) && defined(SDL_UINT64_C))
+
 #ifdef SDL_WIKI_DOCUMENTATION_SECTION
 
 /**
@@ -298,6 +300,8 @@ void *alloca(size_t);
 #define SDL_UINT64_C(c)  c ## ULL
 #endif
 
+#endif /* !(defined(SDL_SINT64_C) && defined(SDL_UINT64_C)) */
+
 /**
  *  \name Basic data types
  */