Add an option to genode.core.children and genode.init.children
for specifying a Nic driver for the exclusive use of the child
for which it is added. This mechanism is to support the nic_router
but it is reusable for arbitrary children.
Make the config.genode.boot.storeBackend option a choice between
a traditional file-system or memory-backed file-system image. Fix
GRUB booting when using a file-system store.
The nova-ahci test shows that this is working.