If one port fails to initialize an error message should indicate the
reason and driver should continue serving the working port(s) and other
HCA(s).

Fixes: e4b2d068 ("IB/ipoib: Remove device when one port fails to init").
Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>