net: atlantic: Define aq_pm_ops conditionally on CONFIG_PM

For s390, gcc with W=1 reports
drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c:458:32: error:
  'aq_pm_ops' defined but not used [-Werror=unused-const-variable=]
  458 | static const struct dev_pm_ops aq_pm_ops = {
      |                                ^~~~~~~~~

The only use of aq_pm_ops is conditional on CONFIG_PM.
The definition of aq_pm_ops and its functions should also
be conditional on CONFIG_PM.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/aquantia/atlantic/aq_pci_func.c

@@ -379,6 +379,7 @@ static void aq_pci_shutdown(struct pci_dev *pdev)
 	}
 }
 
+#ifdef CONFIG_PM
 static int aq_suspend_common(struct device *dev)
 {
 	struct aq_nic_s *nic = pci_get_drvdata(to_pci_dev(dev));
@@ -463,6 +464,7 @@ static const struct dev_pm_ops aq_pm_ops = {
 	.restore = aq_pm_resume_restore,
 	.thaw = aq_pm_thaw,
 };
+#endif
 
 static struct pci_driver aq_pci_ops = {
 	.name = AQ_CFG_DRV_NAME,