RDMA: Move uverbs_abi_ver into struct ib_device_ops

No reason for every driver to emit code to set this, just make it part of
the driver's existing static const ops structure.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>