This patch sets the userxattr field when run in rootless mode.
Fixes: https://github.com/containers/buildah/issues/3503
Patch came from @flouthoc Aditya Rajan <arajan@redhat.com>
[NO TESTS NEEDED] Since this can not be tested in CI/CD system yet.
Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>