s390/time: simply Kconfig dependency

Use HAVE_MARCH_Z9_109_FEATURES to figure out if stckf is available
at compile time.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2 files changed