qemu-timer: Remove function alarm_has_dynticks

qemu-timer: Remove function alarm_has_dynticks

Some time ago, the last time which did not have dynticks was removed,
so now all timers have dynticks.

I also removed a misleading error message for the dynticks timer.
If timer_create fails, there is already an error message, and
QEMU will use the unix timer which also provides dynamic ticks,
therefore dynamic ticks are not disabled.

v2:
Remove two if statements because they were always true
(thanks to Paolo Bonzini for this correction).

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>