ksmbd: use oid registry functions to decode OIDs

[ Upstream commit 29427741 ]

Use look_up_OID to decode OIDs rather than
implementing functions.

Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>