binutils: fix compiling with arch-based distros

binutils: fix compiling with arch-based distros

Arch Linux users have encountered problems with packages that have a dependency on binutils. This error happens when libtool is doing:
  libtool: relink: ...
So change PKG_FIXUP to "patch-libtool".

Fixes error in the form of:
  libtool: install: error: relink `libctf.la' with the above command
           before installing it

Upstream Bug:
https://sourceware.org/bugzilla/show_bug.cgi?id=28545

OpenWrt Bug:
https://bugs.openwrt.org/index.php?do=details&task_id=4149

Acked-by: John Audia <graysky@archlinux.us>
Signed-off-by: Nick Hainke <vincent@systemli.org>