IB/core: Introduce rdma_user_mmap_entry_insert_range() API

Introduce rdma_user_mmap_entry_insert_range() API to be used once the
required key for the given entry should be in a given range.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Link: https://lore.kernel.org/r/20191212100237.330654-2-leon@kernel.org


Signed-off-by: Doug Ledford <dledford@redhat.com>