[coreboot] [RFC] Successful build with GCC 7.2 and IASL 20170831 for coreboot 4.7

Dear coreboot folks, I’d like to propose the following goal for the upcoming coreboot 4.7 release. All boards have to build with GCC 7.2 [1] and IASL 20170831 [2]. For the latter, several Intel boards fail to build [3]. It’d be great if the maintainers looked into it. Thanks, Paul [1] https://review.coreboot.org/20809/ [2] https://review.coreboot.org/21156/ [3] https://ticket.coreboot.org/issues/138