rpm: drop cyrus-sasl dep

rpm: drop cyrus-sasl dep

We link to libsasl2.so, so get a dep on cyrus-sasl-libs automatically.
The dep on cyrus-sasl-gssapi gets us the mechanism that matches our
default config.

The 'cyrus-sasl' package merely contains some man pages and the
saslauthd daemon, which is not required by libvirt. This dep appears
to have been redundant since we first added in

  commit 1b1d647439059b7e10fb94e1ade227fb695d7110
  Author: Daniel P. Berrangé <berrange@redhat.com>
  Date:   Wed Dec 5 15:24:15 2007 +0000

    Initial integration of SASL authentication, working for Kerberos only

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>