mlxsw: reg: Add Management Binary Code Transfer Register

The MBCT register allows to transfer binary INI codes from the host to
the management FW by transferring it by chunks of maximum 1KB.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>