'make distcheck' fails from a directory configured --without-lxc:

  GEN      virt-login-shell.1
Can't write-open ../../tools/virt-login-shell.1: Permission denied at /usr/bin/pod2man line 69.

* tools/Makefile.am (EXTRA_DIST): Ship pre-built man page.
Signed-off-by: NEric Blake <eblake@redhat.com>