irqchip/stm32mp-exti: Use of_property_present() for non-boolean properties

The use of of_property_read_bool() for non-boolean properties is deprecated
in favor of of_property_present() when testing for property presence.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Antonio Borneo <antonio.borneo@foss.st.com>
Link: https://lore.kernel.org/all/20241104190836.278117-1-robh@kernel.org