stdenv-bootstrap-tools: don't copy obsolete libutil from glibc

Starting from glibc 2.34, all functionality previously implemented in
libpthread, libdl, libutil and libanl are now integrated into libc.

https://lists.gnu.org/archive/html/info-gnu/2021-08/msg00001.html

As loongarch64 support was merged into glibc after 2.34, libutil.so is
no longer in there, thus breaking bootstrap.

loongson-community/discussions#29

libdl is not removed because bash still links against it, and libpthread
is not removed because xgcc depends on it to build libatomic.

Author: Aleksanaa

pkgs/stdenv/linux/stdenv-bootstrap-tools.nix

@@ -66,7 +66,6 @@ stdenv.mkDerivation (finalAttrs: {
           cp -d ${libc.out}/lib/libnsl*.so* $out/lib
         ''
         + ''
-          cp -d ${libc.out}/lib/libutil*.so* $out/lib
           cp -d ${libc.out}/lib/libnss*.so* $out/lib
           cp -d ${libc.out}/lib/libresolv*.so* $out/lib
           # Copy all runtime files to enable non-PIE, PIE, static PIE and profile-generated builds