PM / ACPI: Remove acpi_sleep=s4_nonvs

acpi_sleep=s4_nonvs is superseded by acpi_sleep=nonvs, so remove it.

Signed-off-by: WANG Cong <amwang@redhat.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Len Brown <lenb@kernel.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>