irq: remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY

Now that all users of CONFIG_HANDLE_DOMAIN_IRQ perform the irq entry
work themselves, we can remove the legacy
CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY behaviour.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>