Remove patches that are no longer needed:
* GtkButton-do-no-prelight: merged upstream
* Duplicate-the-exec-string: upstream decided this behaviour is incorrect
* cellrenderer-cairo: Cairo isn't the performance bottleneck it once was, drop
* configure-nm: resolved upstrea
* configurefix.patch: not applied
* run-iconcache: not needed when building tarballs, and if gtk-update-icon-cache
is needed at build time (e.g. user is customising default icon theme) then
they can add a dependency on gtk-update-icon-cache-native.
Also remove mention of patches that have been commented out for a long time.
Signed-off-by: Ross Burton <ross.burton@intel.com>
