s3/4: libsmbclient test. Test using smbc_telldir/smbc_lseekdir with smbc_readdir...

s3/4: libsmbclient test. Test using smbc_telldir/smbc_lseekdir with smbc_readdir/smbc_readdirplus/smbc_getdents.

Ensure that for file access you can mix any of these
three access methods for directory entries and the
returned names/structs stay in sync across telldir/seekdir
changes.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14094

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Böhme <slow@samba.org>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Tue Sep  3 17:31:29 UTC 2019 on sn-devel-184