Remove i686 from arch=()

FTR, commands used to change arch=() and then verify the changes:

$ sed -Ei "/^arch=/{s/ *?['\"]?i686['\"]? *?//;s/ *$//}" */*/PKGBUILD*

$ grep -r i686 * | grep arch= | grep -v repos

$ svn diff | grep -A 1 ^-[^-] | grep -v -- -- | cut -c2- |
  while IFS=$'\n' read -r l1; IFS=$'\n' read -r l2; do
    echo "$l1 -> $l2"
  done | sort -u

PKGBUILD

@@ -5,7 +5,7 @@ pkgname=dillo
 pkgver=3.0.5
 pkgrel=5
 pkgdesc="A small, fast graphical web browser built on FLTK"
-arch=(i686 x86_64)
+arch=(x86_64)
 url="http://www.dillo.org"
 license=('GPL')
 depends=('fltk' 'libjpeg' 'perl' 'openssl' 'libpng' 'gcc-libs' 'libxcursor'