[libunwind] [libcxxabi] [NFC] Remove deprecated warning from cmake files (PR #72595)

[via cfe-commits]

https://github.com/AdvenamTacet created https://github.com/llvm/llvm-project/pull/72595

`LIBCXXABI_SYSROOT`, `LIBCXXABI_TARGET_TRIPLE` and `LIBCXXABI_GCC_TOOLCHAIN` are not supported anymore. Based on the comment, the warning should be removed after branching for LLVM 15.

>From 5ac6d886dfcbcec26d34ef4b086f4e077dee2410 Mon Sep 17 00:00:00 2001
From: Advenam Tacet <advenam.tacet at trailofbits.com>
Date: Fri, 17 Nov 2023 03:09:59 +0100
Subject: [PATCH] [NFC] Remove deprecated warning from cmake files

`LIBCXXABI_SYSROOT`, `LIBCXXABI_TARGET_TRIPLE` and `LIBCXXABI_GCC_TOOLCHAIN` are not supported anymore. Based on the comment, the warning should be removed after branching for LLVM 15.
---
 libcxxabi/CMakeLists.txt | 5 -----
 libunwind/CMakeLists.txt | 5 -----
 2 files changed, 10 deletions(-)

diff --git a/libcxxabi/CMakeLists.txt b/libcxxabi/CMakeLists.txt
index 6fd4f02c750f5bb..efe830bd2ad6659 100644
--- a/libcxxabi/CMakeLists.txt
+++ b/libcxxabi/CMakeLists.txt
@@ -88,11 +88,6 @@ else()
   set(LIBCXXABI_GENERATED_INCLUDE_DIR "${CMAKE_BINARY_DIR}/include/c++/v1")
 endif()
 
-# TODO: Remove this after branching for LLVM 15
-if(LIBCXXABI_SYSROOT OR LIBCXXABI_TARGET_TRIPLE OR LIBCXXABI_GCC_TOOLCHAIN)
-  message(WARNING "LIBCXXABI_SYSROOT, LIBCXXABI_TARGET_TRIPLE and LIBCXXABI_GCC_TOOLCHAIN are not supported anymore, please use the native CMake equivalents instead")
-endif()
-
 set(LIBCXXABI_LIBCXX_LIBRARY_PATH "" CACHE PATH "The path to libc++ library.")
 set(LIBCXXABI_LIBRARY_VERSION "1.0" CACHE STRING
 "Version of libc++abi. This will be reflected in the name of the shared \
diff --git a/libunwind/CMakeLists.txt b/libunwind/CMakeLists.txt
index 84f8ce296a7410b..248e888619e40ba 100644
--- a/libunwind/CMakeLists.txt
+++ b/libunwind/CMakeLists.txt
@@ -63,11 +63,6 @@ cmake_dependent_option(LIBUNWIND_INSTALL_SHARED_LIBRARY
   "Install the shared libunwind library." ON
   "LIBUNWIND_ENABLE_SHARED;LIBUNWIND_INSTALL_LIBRARY" OFF)
 
-# TODO: Remove this after branching for LLVM 15
-if(LIBUNWIND_SYSROOT OR LIBUNWIND_TARGET_TRIPLE OR LIBUNWIND_GCC_TOOLCHAIN)
-  message(WARNING "LIBUNWIND_SYSROOT, LIBUNWIND_TARGET_TRIPLE and LIBUNWIND_GCC_TOOLCHAIN are not supported anymore, please use the native CMake equivalents instead")
-endif()
-
 if(MINGW)
   set(LIBUNWIND_DEFAULT_TEST_CONFIG "llvm-libunwind-mingw.cfg.in")
 elseif (LIBUNWIND_ENABLE_SHARED)