tegra: usb: Fix device enumeration problem of USB1

A known hardware issue of USB1 port where bit 1 (connect status
change) of PORTSC register will be set after issuing Port Reset
(like "usb reset" in u-boot command line).
This will be treated as an error and stops later device enumeration.

Therefore we clear that bit after Port Reset in order to proceed
later device enumeration.

Signed-off-by: Jim Lin <jilin@nvidia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>