SDL: cmake: use add_definitions for compatibility with cmake 3.0

From d460000b4586ff1a10cf2f7cb4e922db3efb9400 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Mon, 20 Jun 2022 19:29:13 +0200
Subject: [PATCH] cmake: use add_definitions for compatibility with cmake 3.0

---
 CMakeLists.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d9e25577eae..76c457cde3d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -59,7 +59,7 @@ include(${SDL2_SOURCE_DIR}/cmake/sdlchecks.cmake)
 # with large inode numbers
 check_symbol_exists("__GLIBC__" "stdlib.h" LIBC_IS_GLIBC)
 if (LIBC_IS_GLIBC AND CMAKE_SIZEOF_VOID_P EQUAL 4)
-    add_compile_definitions(PRIVATE _FILE_OFFSET_BITS=64)
+    add_definitions(-D_FILE_OFFSET_BITS=64)
 endif()
 
 # See docs/release_checklist.md