RDMA/vmw_pvrdma: Call ib_umem_release on destroy QP path

The QP cleanup did not previously call ib_umem_release,
resulting in a user-triggerable kernel resource leak.

Fixes: 29c8d9eba550 ("IB: Add vmw_pvrdma driver")
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Aditya Sarwade <asarwade@vmware.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Bryan Tan <bryantan@vmware.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/vmw_pvrdma/pvrdma_qp.c

@@ -431,6 +431,13 @@ static void pvrdma_free_qp(struct pvrdma_qp *qp)
 	atomic_dec(&qp->refcnt);
 	wait_event(qp->wait, !atomic_read(&qp->refcnt));
 
+	if (!qp->is_kernel) {
+		if (qp->rumem)
+			ib_umem_release(qp->rumem);
+		if (qp->sumem)
+			ib_umem_release(qp->sumem);
+	}
+
 	pvrdma_page_dir_cleanup(dev, &qp->pdir);
 
 	kfree(qp);