RDMA/bnxt_re: Add support for dmabuf pinned memory regions

RDMA/bnxt_re: Add support for dmabuf pinned memory regions

Support the new verb which indicates dmabuf support.  bnxt doesn't support
ODP. So use the pinned version of the dmabuf APIs to enable bnxt_re
devices to work as dmabuf importer.

Link: https://lore.kernel.org/r/1690790473-25850-2-git-send-email-selvin.xavier@broadcom.com
Signed-off-by: Saravanan Vajravel <saravanan.vajravel@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>