purge references to iconv, its not needed, Android is UTF-8

iconv is a library for converting between different formats.  Since Android
should be all UTF-8, there should be no need for iconv.  Its been working
so far without it, so I'm purging the iconv stuff.

Here's the thread:
http://lists.gnupg.org/pipermail/gnupg-devel/2012-January/026529.html
http://www.gossamer-threads.com/lists/gnupg/devel/56909