check/servise: use cached kdat values for features check

The kerndat_init() is now called before the jump to action handler. This
allows us to directly use kdat without calling to the corresponding
kerndat_*() methods.

✓ travis-ci: success for lazy-pages: update checks for availability of userfaultfd (rev3)
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>