Merge branch 'add-missing-facility-check-to-ptp_s390-driver'

Sven Schnelle says:

====================
Add missing facility check to ptp_s390 driver

This patchset adds a missing facility check and a check that the 'query
physical clock' (PTFF QPT) function is actually available. If it's not
present, no qpt ptp device will be registered. In order to use ptff_query()
in a module, the first patch adds a EXPORT_SYMBOL() to export
ptff_function_mask.
====================

Link: https://patch.msgid.link/20260714130342.1971700-1-svens@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>