ACPI/PCI/IRQ: assign ISA IRQ directly during early boot stages

We do not want to store the SCI penalty in the acpi_isa_irq_penalty[]
table because acpi_isa_irq_penalty[] only holds ISA IRQ penalties and
there's no guarantee that the SCI is an ISA IRQ.  We add in the SCI
penalty as a special case in acpi_irq_get_penalty().

But if we called acpi_penalize_isa_irq() or acpi_irq_penalty_update()
for an SCI that happened to be an ISA IRQ, they stored the SCI
penalty (part of the acpi_irq_get_penalty() return value) in
acpi_isa_irq_penalty[].  Subsequent calls to acpi_irq_get_penalty()
returned a penalty that included *two* SCI penalties.

Fixes: 103544d8

 (ACPI,PCI,IRQ: reduce resource requirements)
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Jonathan Liu <net147@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>