[ARM] Correcting GPIO3 IRQ line definition.

Xvisor device tree format is slightly different from Linux's one.
The IRQ should be written as plain number, and not without specifying the
sharing flag nor the interrupt type.
This although can be written with these specifiers (modifying the driver
accordingly), but it would break Xvisor device tree format.

Also, the IRQ number is the IRQ line, without the 32 base IRQ offset.