fixup! Add build/pkg-install.sh.

Author: dot-asm

build/pkg-install.sh

@@ -30,6 +30,7 @@ git clone ${SRC:-"https://github.com/supranational/blst"} blst.$$
  cd blst.$$
  tag=`git tag --sort=v:refname | tail -1`
  git checkout --detach ${tag}
+ tag=`expr substr $tag 2 8`
  ./build.sh "$@"
  cp libblst.a "${DST}/.."
  cp bindings/blst.h* "${DST}/../../include"