x86: apic - get rid of local_apic_timer_verify_ok

We are able to use clock_event_device as it's done in
64bit apic code so lets get rid of local_apic_timer_verify_ok
variable.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>