IB/srp: Always initialize use_fast_reg and use_fmr

Avoid that mapping fails due to use_fast_reg != 0 or use_fmr != 0
if both member variables should be zero (if never_register == 1 or
if neither FMR nor FR is supported). Remove an initialization that
became superfluous due to changing a kmalloc() into a kzalloc()
call.

Fixes: 509c5f33f4f6 ("IB/srp: Prevent mapping failures")
Cc: Sagi Grimberg <sai@grimberg.m>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/ulp/srp/ib_srp.c

@@ -3526,7 +3526,7 @@ static void srp_add_one(struct ib_device *device)
 	int mr_page_shift, p;
 	u64 max_pages_per_mr;
 
-	srp_dev = kmalloc(sizeof *srp_dev, GFP_KERNEL);
+	srp_dev = kzalloc(sizeof(*srp_dev), GFP_KERNEL);
 	if (!srp_dev)
 		return;
 
@@ -3586,8 +3586,6 @@ static void srp_add_one(struct ib_device *device)
 						   IB_ACCESS_REMOTE_WRITE);
 		if (IS_ERR(srp_dev->global_mr))
 			goto err_pd;
-	} else {
-		srp_dev->global_mr = NULL;
 	}
 
 	for (p = rdma_start_port(device); p <= rdma_end_port(device); ++p) {