ACPI: APEI: mark apei_hest_parse() static

apei_hest_parse() is only used in hest.c, so mark it static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
[ rjw: Minor subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>