x86/pci: fix warnings in subsys_initcall functions

Signed-off-by: Robert Richter <robert.richter@amd.com>
Cc: Robert Richter <robert.richter@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/pci/legacy.c b/arch/x86/pci/legacy.c
index d8b6e92..132876c 100644
--- a/arch/x86/pci/legacy.c
+++ b/arch/x86/pci/legacy.c
@@ -66,5 +66,7 @@
 	pci_numa_init();
 #endif
 	pcibios_init();
+
+	return 0;
 }
 subsys_initcall(pci_subsys_init);