Add masking of regular IRQ devices and fix IRQ clash issue

[Deniz-Eren]

Providing compile time option to mask IRQ at the IRQ or pulse handler.

There is enough question in mind as to where the IRQ should be masked; at the ISR or at the pulse handler.

To facilitate experimentation we implement 2 new compile time configurations config/CONFIG_QNX_INTERRUPT_MASK_ISR and config/CONFIG_QNX_INTERRUPT_MASK_PULSE.

The reason we don't just use config/CONFIG_QNX_INTERRUPT_ATTACH_EVENT is because this function only masks regular IRQs and not MSI/MSI-X interrupt vectors.

Currently the default and recommended configurations are config/CONFIG_QNX_INTERRUPT_ATTACH with config/CONFIG_QNX_INTERRUPT_MASK_PULSE.

[Deniz-Eren]

Major improvements to robustness of interrupt handling and an IRQ handling issue fixed.

• Eliminated the possibility of IRQ handler clash bettwen transmission IRQ handler and queue wake-up IRQ handler.
• IRQ handlers have been refactored to be more efficient.
• IRQ masking has been enabled for regular IRQ devices.