libpayload: Fix unused function warning in EHCI stack

The function dump_qh() was added a while back but never used.
Hide it behind USB_DEBUG so it doesn't cause warnings when not
debugging the USB stack.

Change-Id: Idb3c7bb214895ef82676d181836a578bf161e8e0
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Reviewed-on: http://review.coreboot.org/2909
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martin.roth@se-eng.com>
1 file changed