Fix GCC 6 valid warnings about misleading indendations

It's currently producing a lot of false positives, but a few are
actually valid.

See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69029,
 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69122

 and some others.

Change-Id: I24a735698d3c4a719fc9ffff1425f29d7b5a3458
Reviewed-by: Olivier Goffart (Woboq GmbH) <ogoffart@woboq.com>