Move USB ports from the common devicetree to the variants' overridetree
as they differ at least for X11SSH-TF and X11SSM-F.
Change-Id: I9bee3a8f6185296cadcee013a8dbe8dca256bf0b
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36139
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Rudolph <siro@das-labor.org>