Check sanity of CMAKE helpers relative to USES

[adridg]

Summary

If a CMAKE helper is used (e.g. CMAKE_ARGS, or <foo>_CMAKE_ON)
then that only makes sense if cmake is actually used (i.e. is in
USES).

Test Plan

Run against audio/fmit, in r488406 and in HEAD.

[adridg]

Dunno why I had bdrewery in mind here.

[adridg]

ports-mgmt/portlint/src/portlint.pl

1793 ↗

(On Diff #54886)

That's an unrelated typo-fix.

1814 ↗

(On Diff #54886)

@tcberner suggests that an OPTION shouldn't switch the build system, so this checking may not be needed, which would simplify things a bit.