This patch adds support for allocating, deallocating and registering a new
device memory type, STEERING_SW_ICM.  This memory can be allocated and
used by a privileged user for direct rule insertion and management of the
device's steering tables.

The type is provided by the user via the dedicated attribute in the
alloc_dm ioctl command.
Signed-off-by: NAriel Levkovich <lariel@mellanox.com>
Reviewed-by: NEli Cohen <eli@mellanox.com>
Reviewed-by: NMark Bloch <markb@mellanox.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>