RDMA/qib: Remove outdated driver

The qib Infiniband device has long been decommissioned from distros and
unsupported by the company. We have kept it going in a compile only mode
for a while now and it's time to remove the driver. It has a number of
issues that are never going to be addressed and is a hindrance to
improving hfi1 and rdmavt.

Link: https://patch.msgid.link/r/174836076755.2436819.5981097575800950899.stgit@awdrv-04.cornelisnetworks.com


Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>