xhci: tegra: Parameterize mailbox register addresses

Tegra194 XUSB host controller has rearranged mailbox registers. This
commit makes mailbox registers address a part of "soc" data so that
xhci-tegra driver can be used for Tegra194.

Signed-off-by: JC Kuo <jckuo@nvidia.com>
Link: https://lore.kernel.org/r/20191004162906.4818-2-jckuo@nvidia.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>