parted: properly link with libiconv

parted: properly link with libiconv

parted uses libiconv but doesn't link with it. All the checks are there
in configure, but the Makefile.am doesn't add it to the link. Add a
patch to fix this.

Also add an optional dependency on libiconv, so it is reproducible.

While we're at it, regenerate the existing patches on top of v3.2, and
make patch 0003 a properly git formatted one.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Cc: srg.venema@gmail.com
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>