colibri_t20: fix ulpi reset polarity

colibri_t20: fix ulpi reset polarity

Fix ULPI reset polarity which caused a hard hang on Colibri T20 upon
attempting to start the USB subsystem:

This fixes my late commit d5a24d8b53d350364bd429b7104ec369b817e4b8
(colibri_t20: fix usb operation and controller order) inadvertently
having overwritten Stephen's previous commit
2f6a7e8ce5df8b99d84bfd486c6f99d92322ce04 (ARM: tegra: fix USB ULPI PHY
reset signal inversion confusion).

While at it also fix comment about on-module USB port.

Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Signed-off-by: Tom Warren <twarren@nvidia.com>