clocksource/drivers/arm_arch_timer_mmio: Prevent driver unbind

clocksource/drivers/arm_arch_timer_mmio: Prevent driver unbind

Clockevents cannot be deregistered so suppress the bind attributes to
prevent the driver from being unbound and releasing the underlying
resources after registration.

Fixes: 4891f01527bb ("clocksource/drivers/arm_arch_timer: Add standalone MMIO driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://patch.msgid.link/20251111153226.579-2-johan@kernel.org