s3: smbd: Fix the SMB2 server to pass SMB2-PATH-SLASH.

s3: smbd: Fix the SMB2 server to pass SMB2-PATH-SLASH.

[MS-FSA] 2.1.5.1 Server Requests an Open of a File

Windows pathname specific processing.

Always disallow trailing /, and also \\ on FILE_NON_DIRECTORY_FILE.

We need to check this before the generic pathname parser
as the generic pathname parser removes any trailing '/' and '\\'.

Currently this is SMB2 only, but we could also add this
check to the SMB1 NTCreateX calls if ultimately neded.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
Autobuild-User(master): Ralph Böhme <slow@samba.org>
Autobuild-Date(master): Wed Oct  2 09:31:40 UTC 2019 on sn-devel-184