clocksource/drivers/vf-pit: Unify the function name for irq ack
Most the function are under the form pit_timer_*, let's change the
interrupt acknowledgment function name to have the same format.
No functional changes intended.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20250804152344.1109310-18-daniel.lezcano@linaro.org