vme: Convert VME core to register as a subsystem

Previously, VME bridge support was treated as any other driver (using
module_init() macro), but if VME bridge and vme_user (staging) drivers
were compiled into the kernel, then vme_user would attempt to register
itself before the VME core support had been loaded. This would result
in a kernel panic.

The load order of these built-in drivers is based on the order in which
drivers/staging/vme and driver/vme are compiled.

This patch changes the VME core driver to use the subsys_initcall()
macro which ensures that it is loaded before all other VME drivers
regardless of the order in which they are compiled.
Tested-by: Aaron Sierra <asierra@xes-inc.com>
Signed-off-by: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/vme/Kconfig

@@ -3,7 +3,7 @@
 #
 
 menuconfig VME_BUS
-	tristate "VME bridge support"
+	bool "VME bridge support"
 	depends on PCI
 	---help---
 	  If you say Y here you get support for the VME bridge Framework.

drivers/vme/vme.c

@@ -1525,9 +1525,5 @@ static void __exit vme_exit(void)
 	bus_unregister(&vme_bus_type);
 }
 
-MODULE_DESCRIPTION("VME bridge driver framework");
-MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com");
-MODULE_LICENSE("GPL");
-
-module_init(vme_init);
+subsys_initcall(vme_init);
 module_exit(vme_exit);