[PARISC] Add chassis_power_off routine

Define a chassis_power_off routine that machines which have a way
to turn off the power supply can hook into. Formerly they were
using pm_power_off, which is now being used by generic code. Make
lasi.c use chassis_power_off instead of pm_power_off.

Note, all machines need to call machine_power_off so that the
switch can power off the machine, though halt -p may not necessarily
be able to work properly on the machine.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/drivers/parisc/lasi.c b/drivers/parisc/lasi.c
index d043a8a..cb3d281 100644
--- a/drivers/parisc/lasi.c
+++ b/drivers/parisc/lasi.c
@@ -166,6 +166,7 @@
 int __init
 lasi_init_chip(struct parisc_device *dev)
 {
+	extern void (*chassis_power_off)(void);
 	struct gsc_asic *lasi;
 	struct gsc_irq gsc_irq;
 	int ret;
@@ -222,7 +223,7 @@
 	 * ensure that only the first LASI (the one controlling the power off)
 	 * should set the HPA here */
 	lasi_power_off_hpa = lasi->hpa;
-	pm_power_off = lasi_power_off;
+	chassis_power_off = lasi_power_off;
 	
 	return ret;
 }