SMB3: incorrect file id in requests compounded with open

See MS-SMB2 3.2.4.1.4, file ids in compounded requests should be set to
0xFFFFFFFFFFFFFFFF (we were treating it as u32 not u64 and setting
it incorrectly).

Signed-off-by: Steve French <stfrench@microsoft.com>
Reported-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>