[release] Add cmake as an extra tarball and not bundle it

[kwk]

Summary

Revert "Add cmake/ to release tarballs via concatenation"

This reverts commit 3a33664e8838e8b77acd1bbb13b1cf5e580a1077.

Revert "Add cmake to source release tarballs"

This reverts commit 32a0482a65b86cf0d84ea7e784cca9852df5c67c.

[aaronpuchert]

Looks good to me.

[aaronpuchert]

You might also mention that this solves #54716 (in my understanding).

llvm/utils/release/export.sh

 #!/bin/bash
 #===-- tag.sh - Tag the LLVM release candidates ----------------------------===#
 #
 # Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 # See https://llvm.org/LICENSE.txt for license information.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 #
 #===------------------------------------------------------------------------===#
 #
 # Create branches and release candidates for the LLVM release.
 #
 #===------------------------------------------------------------------------===#
 
 set -e
 
-projects="llvm clang compiler-rt libcxx libcxxabi libclc clang-tools-extra polly lldb lld openmp libunwind flang"
+projects="llvm clang cmake compiler-rt libcxx libcxxabi libclc clang-tools-extra polly lldb lld openmp libunwind flang"
 
 release=""
 rc=""
 yyyymmdd=$(date +'%Y%m%d')
 snapshot=""
 template='${PROJECT}-${RELEASE}${RC}.src.tar.xz'
 
 usage() {
if [ -z "$snapshot" ]; then
                 tar -C test-suite-$release$rc.src --strip-components=1 -xzf -
         fi
         echo "Creating tarball for test-suite ..."
         tar --sort=name --owner=0 --group=0 \
             --pax-option=exthdr.name=%d/PaxHeaders/%f,delete=atime,delete=ctime \
             -cJf test-suite-$release$rc.src.tar.xz test-suite-$release$rc.src
     fi
 
-    # Package up top-level cmake directory so that we can append it to all projects.
-    tmp_dir=$(mktemp -d)
-    cmake_archive_file=$tmp_dir/cmake.tar
-    trap "rm -rv $tmp_dir" EXIT
-    pushd $llvm_src_dir
-    git archive -o $cmake_archive_file $tree_id cmake/
-    popd
-
     for proj in $projects; do
         echo "Creating tarball for $proj ..."
         pushd $llvm_src_dir/$proj
-        tmp_archive_file=$tmp_dir/$proj.tar
-        git archive --prefix=$proj-$release$rc.src/ -o $tmp_archive_file $tree_id .
-        tar -Af $tmp_archive_file $cmake_archive_file
-        xz < $tmp_archive_file > $target_dir/$(template_file $proj)
+        git archive --prefix=$proj-$release$rc.src/ $tree_id . | xz >$target_dir/$(template_file $proj)
         popd
     done
 }
 
 while [ $# -gt 0 ]; do
     case $1 in
         -release | --release )
             shift