ipa-sam: replace encode_nt_key() with E_md4hash()
Since ipa-sam is running as part of smbd is it safe to use the
E_md4hash() from Samba. This way ipa-sam does not depend on other crypto
libraries which might depend on other rules like e.g. FIPS mode.
Resolves https://pagure.io/freeipa/issue/7026
Reviewed-By: Alexander Bokovoy <abokovoy@redhat.com>
Reviewed-By: Stanislav Laznicka <slaznick@redhat.com>