Windows: always open dscp in smb_ReceiveNTTranCreate

Windows: always open dscp in smb_ReceiveNTTranCreate

There were two code paths in smb_ReceiveNTTranCreate that included
asserts in case the directory cm_scache_t object had not been
evaluated.  RT129299 contains a report that at least one of
them had been tripped in production.  There is no reason to avoid
evaluating the directory scp.  It must exist in the cache and
obtaining a reference in all cases simplifies the logic of this
overly complex function.

FIXES 129299

Reviewed-on: http://gerrit.openafs.org/4967
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Tested-by: Jeffrey Altman <jaltman@openafs.org>
(cherry picked from commit 27af8b4b537236d8c678465d034721dd220641c8)

Change-Id: Id4abbc179fc1410b3d45bfc9c69814f683ebcb57
Reviewed-on: http://gerrit.openafs.org/4977
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>