s3/selftest: Move samba3.blackbox.smbclient_ntlm.plain to nt4_dc_smb1
samba3.blackbox.smbclient_ntlm.plain will fail in test environment
that doesn't support SMB1 so move to nt4_dc_smb1
This test only fails with options that require it to communicate over
SMB1, there are sibling tests that test against >= SMB2 so also we
remove the skip_smb1_fail entry as this test doen't need porting
(for this env)
Signed-off-by: Noel Power <noel.power@suse.com> Reviewed-by: Ralph Boehme <slow@samba.org>