sfc: Fix some formatting errors reported by checkpatch

Fix the following errors and warnings:

ERROR: trailing whitespace
ERROR: spaces required around that '=' (ctx:VxV)
WARNING: please, no space before tabs

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

drivers/net/ethernet/sfc/mcdi_mac.c

@@ -141,5 +141,5 @@ static bool efx_mcdi_mac_check_fault(struct efx_nic *efx)
 const struct efx_mac_operations efx_mcdi_mac_operations = {
 	.reconfigure	= efx_mcdi_mac_reconfigure,
 	.update_stats	= efx_port_dummy_op_void,
-	.check_fault 	= efx_mcdi_mac_check_fault,
+	.check_fault	= efx_mcdi_mac_check_fault,
 };