Request for inclusion of f73b3cc39c84 ("objtool: Clobber user CFLAGS variable") in -stable

[Nathan Chancellor]

Hi Greg and Sasha,

We received a report of an objtool build failure with clang related to
-Wunused-parameter [1], which turned out to be related to the distro's
CFLAGS. Josh patched this up in commit f73b3cc39c84 ("objtool: Clobber
user CFLAGS variable"), could it be added to -stable whenever
applicable? Looks like it will pick cleanly to 4.19 but it can be
applied to 4.14 with context differences.

Josh and Peter, would you be interested in patches that fix and then
enable -Wunused-parameter? There are only a couple of warnings. Let
me know, I can send my patches along.

[1]: https://github.com/ClangBuiltLinux/linux/issues/676

Cheers,
Nathan