s3: smbd: Tweak the logic of smb2_file_rename_information().

s3: smbd: Tweak the logic of smb2_file_rename_information().

There's no point in calling filename_convert() and then
just ignoring the returned smb_fname if it's a raw stream name.
Only call filename_convert() if we know it isn't a raw stream
name.

Ignore stream/non-stream mismatches in src and dst in
smb2_file_rename_information, let rename_internals_fsp()
take care of that as the error returns inside rename_internals_fsp()
are tested by raw.streams.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>