Set up 3rdparty/libhwbase

`libhwbase` is a SPARK library that contains some basic support for i/o
access, debugging, timers. Just what I put around `libgfxinit`, to make
it build standalone.

Change-Id: I1918680c14696215522e1c5dae072235bb4e71a3
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: https://review.coreboot.org/16948
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
3 files changed