Instead of trying to manage IRQ numbers on itself, utilise the
pci_irq_vector() function to do this, which will take care of correct IRQ
numbering for MSI and non-MSI IRQs. While at it, request and enable MSI-X
interrupts for hardware (boards and cards) that support this.

Picked up from the upstream dddvb-0.9.33 release.
Signed-off-by: Daniel Scheller <d.scheller@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>