Update to 7.4.0 [1]

• Fix build on ARMv6 [2]
• While I'm here, remove duplicate PLIST_SUB which is already handled by OPTIONS_SUB=yes

Changes: https://github.com/nodejs/node/blob/master/doc/changelogs/CHANGELOG_V7.md

		https://nodejs.org/en/blog/release/v7.4.0/

PR: 215775 [1], 215044 [2]
Submitted by: Bradley T. Hughes <bradleythughes@fastmail.fm> (maintainer) [1],

		Peter Laursen <plaursen@kobalt.dk> [2]