RDMA/ocrdma: Remove use of idr use pci bdf instead

Removing the use of IDR variable just to name the function ids. Using the
PCI_FUNC(pdev->devfn) instead to create the device name, associated
resources and to print driver into at various places.

Reported-by: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>