dde_kit: enable pci lookup by device_class

Instead of trying all PCI devices by a specific PCI driver, now the device or
the device class can be limited to the one actually supported by the specific
driver.
dde_kit: support to allocate DMA buffer per device
dde_ipxe: alloc DMA memory via dde_kit
lwip: adjust run script to run with new pci_drv
nova: don't try to prepare UTCB in case of vCPU

vCPU has no UTCB.

Fixes #673
nova: optimize unmap path

Directly unmap memory range instead of looking first it up and then unmap it.

Prerequisite for #675
nova: zero out space behind rom modules

Fixes #675
vancouver: adjust run script to use acpi+iommu
doc: Update components.txt
Release notes for Genode 13.02