IB/core: Introduce protected memory regions

This commit introduces verbs for creating/destoying memory
regions which will allow new types of memory key operations such
as protected memory registration.

Indirect memory registration is registering several (one
of more) pre-registered memory regions in a specific layout.
The Indirect region may potentialy describe several regions
and some repitition format between them.

Protected Memory registration is registering a memory region
with various data integrity attributes which will describe protection
schemes that will be handled by the HCA in an offloaded manner.
These memory regions will be applicable for a new REG_SIG_MR
work request introduced later in this patchset.

In the future these routines may replace or implement current memory
regions creation routines existing today:
- ib_reg_user_mr
- ib_alloc_fast_reg_mr
- ib_get_dma_mr
- ib_dereg_mr

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>