Make sure to re-enable SCI after an ACPI suspend

According to the ACPI spec, it should be enabled on return from suspend,
but bugs happen.  Apparently especially on the Apple Intel Macs.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
index 07bc6df..8920e8c 100644
--- a/drivers/acpi/pci_link.c
+++ b/drivers/acpi/pci_link.c
@@ -812,6 +812,9 @@
 
 	ACPI_FUNCTION_TRACE("irqrouter_resume");
 
+	/* Make sure SCI is enabled again (Apple firmware bug?) */
+	acpi_set_register(ACPI_BITREG_SCI_ENABLE, 1, ACPI_MTX_DO_NOT_LOCK);
+
 	acpi_in_resume = 1;
 	list_for_each(node, &acpi_link.entries) {
 		link = list_entry(node, struct acpi_pci_link, node);