USB: ce4100: Add support for CE4100 EHCI IP block to EHCI driver

This patch adds support for the EHCI IP block present on the Intel
CE4100.

Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
CC: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>