The pc_discover component selects device drivers according to the PCI bus
and platform information. It consumes the 'devices' report of the platform
driver and a pristine 'board-pc' option featuring all potential drivers
(marked as 'enabled: discover'). In return, it reports a modified 'board-pc'
deploy option with only the drivers enabled that match the hardware.

Note that the report session created by this component is immediately closed
after reporting. Hence, it can only be combined with report services like
fs_report that store reports independently of the lifetime of the report
sessions.
