Make MRC vs native a config rather than making a separate chipset for it.

Tested by making lenovo x230 configurable despite pretty MRC bugs.

Change-Id: Ia2a123f24334f5cd5f42473b7ce7f3d77c0e65b7
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: https://review.coreboot.org/13658
Tested-by: build bot (Jenkins)
Reviewed-by: Martin Roth <martinroth@google.com>
28 files changed