Use -O instead of -O2.

* This fixes crash at opening settings window on NetBSD 5.2.
Remove unused block, and make pkglint more happy.
Wrong line as \'BUILD_TARGET= build\' was included, resulting almost empty package, sorry.
Add w3m-load.elc onto PLIST, due to upstream change
   2013-08-13  Kevin Ryde  <user42@zip.com.au>
        * w3mhack.el (w3mhack-module-list): Remove w3mhack-load-file from the
        modules not to be byte compiled, so that it is byte compiled.
        (w3mhack-generate-load-file): Remove no-byte-compile from w3m-load.el.
Remove utf8.el{,c}. Related upstream log is following. (But
timing does not explain recent inconsistency, sorry. Need check ?)
  2012-08-04  Kazuhiro Ito  <kzhr@d1.dion.ne.jp>
        * WL-ELS (ELMO-MODULES): Do not include utf7.el when Emacs has
        utf-7-imap coding system.