misc: tegra-baseband: remove EHCI info from board file

misc: tegra-baseband: remove EHCI info from board file

This is a WAR after EHCI moves to DT. We shall try to work out a
solution to load/unload EHCI from DT in modem driver. This change only
moves the statically defined tegra_ehci_device and platform data from
board file to modem driver to dynamically load/unload EHCI.

Bug 1522530

Change-Id: I4c1a291dab93157f27e88bde8dbdf3a5dd5b76e2
Signed-off-by: Mark Kuo <mkuo@nvidia.com>
Reviewed-on: http://git-master/r/452872
Reviewed-by: Suresh Mangipudi <smangipudi@nvidia.com>
Tested-by: Suresh Mangipudi <smangipudi@nvidia.com>
Reviewed-by: Venkat Moganty <vmoganty@nvidia.com>