mlxsw: pci: Fix missing error checking

I accidentally removed the error checking after issuing the reset.
Restore it.

Fixes: f257c73 ("mlxsw: pci: Add support for new reset flow")
Reported-by: Coverity Scan <scan-admin@coverity.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/pci.c

@@ -1561,6 +1561,8 @@ mlxsw_pci_reset(struct mlxsw_pci *mlxsw_pci, const struct pci_device_id *id)
 		pci_dbg(pdev, "Starting software reset flow\n");
 		err = mlxsw_pci_reset_sw(mlxsw_pci);
 	}
+	if (err)
+		return err;
 
 	err = mlxsw_pci_sys_ready_wait(mlxsw_pci, id, &sys_status);
 	if (err) {