usbdebug: Refactor early enable

Always sanity check for EHCI class device and move
PCI function power enablement up.

Change-Id: I1eebe813fbb420738af2d572178213fc660f392a
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/20826
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
13 files changed