RDMA: Rename port_callback to init_port

Most provider routines are callback routines which ib core invokes.
_callback suffix doesn't convey information about when such callback is
invoked. Therefore, rename port_callback to init_port.

Additionally, store the init_port function pointer in ib_device_ops, so
that it can be accessed in subsequent patches when binding rdma device to
net namespace.

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

drivers/infiniband/hw/qedr/main.c

@@ -290,7 +290,7 @@ static int qedr_register_device(struct qedr_dev *dev)
 	ib_set_device_ops(&dev->ibdev, &qedr_dev_ops);
 
 	dev->ibdev.driver_id = RDMA_DRIVER_QEDR;
-	return ib_register_device(&dev->ibdev, "qedr%d", NULL);
+	return ib_register_device(&dev->ibdev, "qedr%d");
 }
 
 /* This function allocates fast-path status block memory */