SDL: cmake: Remove warning about CFLAGS environment variable.

SDL Commits
1 
From ab09f3dae5bf89f17ef92d78ff7e5d2fde9c14b8 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Thu, 30 Sep 2021 10:00:58 -0400
Subject: [PATCH] cmake: Remove warning about CFLAGS environment variable.

CMake 3.11.0 respects this environment var.

Fixes #4681.
---
 CMakeLists.txt | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index be8103614f..f7cc87d2a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -211,10 +211,6 @@ if(UNIX OR MINGW OR MSYS OR (USE_CLANG AND NOT WINDOWS) OR VITA)
   set(OPT_DEF_LIBC ON)
 endif()
 
-if(NOT ("$ENV{CFLAGS}" STREQUAL ""))
-  message(WARNING "SDL's CMakeLists.txt no longer checks the CFLAGS environment. Please use CMake's CMAKE_C_FLAGS and CMAKE_BUILD_TYPE variables directly.")
-endif()
-
 if(MSVC)
   option(FORCE_STATIC_VCRT "Force /MT for static VC runtimes" OFF)
   if(FORCE_STATIC_VCRT)