PM / ACPI: Move NVS saving and restoring code to drivers/acpi

The saving of the ACPI NVS area during hibernation and suspend and
restoring it during the subsequent resume is entirely specific to
ACPI, so move it to drivers/acpi and drop the CONFIG_SUSPEND_NVS
configuration option which is redundant.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 3d031d0..9cc9f2c 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -24,7 +24,7 @@
 # sleep related files
 acpi-y				+= wakeup.o
 acpi-y				+= sleep.o
-acpi-$(CONFIG_ACPI_SLEEP)	+= proc.o
+acpi-$(CONFIG_ACPI_SLEEP)	+= proc.o nvs.o
 
 
 #