Use single quoting to avoid shell variable expansion in the sed substitutions.
Amend comment to reflect that DSO_LDFLAGS will be set to LDFLAGS from makepkg.
This produces the following change in the modified Makefile:
```
< DSO_LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now-g -pthread -lm -lrt
---
> DSO_LDFLAGS=$(LDFLAGS)
```

There is no signature file for the 0.0.10.1 tarball.  git was previously used between c35f17bb and 7a53931b.

archlinux/devtools!109 (comment 74475)

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