[libc++] Remove warning for `LIBCXX_SYSROOT`, `LIBCXX_TARGET_TRIPLE`, and `LIBCXX_GCC...

Support for these CMake variables has been a warning for a while now.  The
comment indicates to just remove the warning message entirely as anyone impacted
had to have update to new mechanisms in order to use `libc++`.  So, remove the
warning message.

Differential Revision: https://reviews.llvm.org/D141345

diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index eb71ae8..f3b2c10 100644 (file)
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -269,11 +269,6 @@ if (LIBCXX_BUILD_32_BITS)
   message(FATAL_ERROR "LIBCXX_BUILD_32_BITS is not supported anymore when building the runtimes, please specify a full triple instead.")
 endif()
 
-# TODO: Remove this after branching for LLVM 15
-if(LIBCXX_SYSROOT OR LIBCXX_TARGET_TRIPLE OR LIBCXX_GCC_TOOLCHAIN)
-  message(WARNING "LIBCXX_SYSROOT, LIBCXX_TARGET_TRIPLE and LIBCXX_GCC_TOOLCHAIN are not supported anymore, please use the native CMake equivalents instead")
-endif()
-
 # Feature options -------------------------------------------------------------
 option(LIBCXX_ENABLE_EXCEPTIONS "Use exceptions." ON)
 option(LIBCXX_ENABLE_RTTI "Use run time type information." ON)