usb: host: xhci-tegra: Add Tegra186 XUSB support

This commit adds Tegra186 XUSB host mode controller support. This is
very similar to the existing support for Tegra124 and Tegra210, except
that the number of ports and PHYs differs and the IPFS wrapper being
gone.

Signed-off-by: JC Kuo <jckuo@nvidia.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>