sandy/ivy native: dedup romstage.c main()

Change-Id: I9909a5b2bdb4b59219db6304fa4332802fe0301c
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/7127
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
sandybridge: Kill CONFIG_HAVE_MRC_CACHE

Change-Id: I54955fa44d126b7a3d382f57b4aa0dac01688104
Signed-off-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-on: http://review.coreboot.org/7129
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>