device: Stop and output time in `scan_bus()`

Output how long it took to scan a bus.

Note, that the function `scan_bus()` is called recursively.

Change-Id: I6335e10db783f092ea18d3a1c79f93135bee5826
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-on: http://review.coreboot.org/12103
Tested-by: build bot (Jenkins)
Tested-by: Raptor Engineering Automated Test Stand <noreply@raptorengineeringinc.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
1 file changed