nvmet: Use nvmet_is_port_enabled helper for pi_enable

Remove code duplication.
Signed-off-by: Israel Rukshin <israelr@nvidia.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/configfs.c

@@ -266,10 +266,8 @@ static ssize_t nvmet_param_pi_enable_store(struct config_item *item,
 	if (strtobool(page, &val))
 		return -EINVAL;
 
-	if (port->enabled) {
-		pr_err("Disable port before setting pi_enable value.\n");
+	if (nvmet_is_port_enabled(port, __func__))
 		return -EACCES;
-	}
 
 	port->pi_enable = val;
 	return count;