ACPICA: acpi_get_sleep_type_data: Reduce warnings

ACPICA commit 7bb77313091e52a846df4c9c2bea90be31bfb9d8

Eliminate warnings for "not found" _Sx errors, since these
are optional. Original NOT_FOUND status is still returned.

Original changes by Prarit Bhargava.
ACPICA BZ 1208.

Link: https://github.com/acpica/acpica/commit/7bb77313
Link: https://bugs.acpica.org/show_bug.cgi?id=1208


Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>