This has an active upstream so will presumably be fixed upstream at
some point.
Reviewed by: emaste
Differential Revision: https://reviews.freebsd.org/D39525
Prefer ${SRCTOP}/foo over ${.CURDIR}/../../foo and ${SRCTOP}/usr.bin/foo
over ${.CURDIR}/../foo for paths in Makefiles.
Differential Revision: https://reviews.freebsd.org/D9932
Sponsored by: Netflix
Silence on: arch@ (twice)
