smbd: Avoid an if-statement per read/write in the non-clustered case

smbd: Avoid an if-statement per read/write in the non-clustered case

Without clustering, fsp->brlock_rec will never be set anyway. In the
clustering case we can't use the seqnum trick, so this is slow enough
that the additional if-statement does not matter in this case anyway. In
the non-clustered case it might. Have not measured it, but every little
bit helps I guess.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>