ACPI: fix CONFIG_NET=n acpi_bus_generate_netlink_event build failure

drivers/acpi/event.c:243: error: 'acpi_generate_netlink_event' undeclared
here (not in a function)

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/event.c b/drivers/acpi/event.c
index a2b9304..5c95863 100644
--- a/drivers/acpi/event.c
+++ b/drivers/acpi/event.c
@@ -240,7 +240,7 @@
 	return 0;
 }
 
-EXPORT_SYMBOL(acpi_generate_netlink_event);
+EXPORT_SYMBOL(acpi_bus_generate_netlink_event);
 
 static int acpi_event_genetlink_init(void)
 {