rockchip/rk3399: Add a stub implementation of the rk3399 SOC

Most things still need to be filled in, but this will allow
us to build boards which use this SOC.

BRANCH=none
BUG=chrome-os-partner:51537
TEST=with the rest of the patches applied Kevin board can be booted to
     Linux login propmt.

Change-Id: I6f2407ff578dcd3d0daed86dd03d8f5f4edcac53
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 27dfc39efe95025be2271e2e00e9df93b7907840
Original-Change-Id: I6f2407ff578dcd3d0daed86dd03d8f5f4edcac53
Original-Signed-off-by: huang lin <hl@rock-chips.com>
Original-Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/332385
Reviewed-on: https://review.coreboot.org/13915
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
11 files changed