x86, olpc: Add XO-1 poweroff support

Add a pm_power_off handler for the OLPC XO-1 laptop.

The driver can be built modular and follows the behaviour of the
APM driver, setting pm_power_off to NULL on unload. However, the
ability to unload the module will probably be removed (with a simple
__module_get(THIS_MODULE)) if/when XO-1 suspend/resume support is
added to this file at a later date.

Signed-off-by: Daniel Drake <dsd@laptop.org>
LKML-Reference: <20101010094032.9AE669D401B@zog.reactivated.net>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index c255255..0bcb876 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2066,6 +2066,12 @@
 	  Add support for detecting the unique features of the OLPC
 	  XO hardware.
 
+config OLPC_XO1
+	tristate "OLPC XO-1 support"
+	depends on OLPC
+	---help---
+	  Add support for non-essential features of the OLPC XO-1 laptop.
+
 config OLPC_OPENFIRMWARE
 	bool "Support for OLPC's Open Firmware"
 	depends on !X86_64 && !X86_PAE