smb: client: make use of struct smbdirect_recv_io

smb: client: make use of struct smbdirect_recv_io

This is the shared structure that will be used in
the server too and will allow us to move helper functions
into common code soon.

Cc: Steve French <smfrench@gmail.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Long Li <longli@microsoft.com>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <stfrench@microsoft.com>