Marvell: IcuLib: Rework default interrupt map

The ICU to GIC interrupt mapping was fixed to support
the maximum of two CP11x south bridge units. Rework
the default map to use only the interrupts wired
to controllers supported in the ACPI tables.
Thanks to above all necessary IRQs from the CN913x
SoCs (maximum 3 CP11x) can be mapped and passed to the OS.

Signed-off-by: Marcin Wojtas <mw@semihalf.com>