USB: EHCI: Tegra: Fix wrong register definition

Fix the issue that EHCI registers, hostpc[0] and usbmode_ex,
are not correctly accessed on Tegra3 platform.

Signed-off-by: Jim Lin <jilin@nvidia.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>