inotify-tools: bump to version 3.20.1

Bumping this package to the most recent stable version. Drops the
need for the GCC 6.x patch as a related fix has been merged in [1].

[1]: https://github.com/rvoicilas/inotify-tools/pull/65



Signed-off-by: James Knight <james.d.knight@live.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>