On some systems, EHCI seems to be getting IRQs too early during driver
setup ... before the root hub is allocated, in particular, making trouble
for any code chasing down root hub pointers!  In this case, it seems to
be safe to just ignore the root hub setting.  Thanks to Rafael J. Wysocki
for getting this properly tested.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>