Remove unused `run-qemu.sh`

ci/run-qemu.sh

-#!/usr/bin/env sh
-
-# Initial script which is run inside of all qemu images. The first argument to
-# this script (as arranged by the qemu image itself) is the path to where the
-# libc crate is mounted.
-#
-# For qemu images we currently need to install Rust manually as this wasn't done
-# by the initial run-travis.sh script
-#
-# FIXME: feels like run-travis.sh should be responsible for downloading the
-#        compiler.
-
-set -ex
-
-ROOT="${1}"
-cp -r "${ROOT}/libc" /tmp/libc
-cd /tmp/libc
-
-TARGET="$(cat "${ROOT}/TARGET")"
-export CARGO_TARGET_DIR=/tmp
-
-case $TARGET in
-  *-openbsd)
-    pkg_add cargo gcc%4.9 rust
-    export CC=egcc
-    ;;
-
-  *)
-    echo "Unknown target: ${TARGET}"
-    exit 1
-    ;;
-esac
-
-exec sh ci/run.sh "${TARGET}"