RDMA/qib: Use GUP longterm for PSM page pining

Similar to the core change commit 5f1d43de

 ("IB/core: disable memory
registration of filesystem-dax vmas")

PSM should be prevented from using filesystem DAX pages.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>