PCI: pci-epf-test: Register notifier if only core_init_notifier is enabled

The pci_epf_test_notifier function should be installed also if only
core_init_notifier is enabled. Fix the current logic.

Link: https://lore.kernel.org/r/[e-mail]
Fixes: 5e50ee27d4a5 ("PCI: pci-epf-test: Add support to defer core initialization")
Signed-off-by: Kunihiko Hayashi <[e-mail]>
Signed-off-by: Lorenzo Pieralisi <[e-mail]>
Acked-by: Om Prakash Singh <[e-mail]>
Acked-by: Kishon Vijay Abraham I <[e-mail]>

drivers/pci/endpoint/functions/pci-epf-test.c

···
 	if (ret)
 		epf_test->dma_supported = false;
 
-	if (linkup_notifier) {
+	if (linkup_notifier || core_init_notifier) {
 		epf->nb.notifier_call = pci_epf_test_notifier;
 		pci_epc_register_notifier(epc, &epf->nb);
 	} else {