completion: fix function name

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
(transplanted from a57b8a45ea26c16a8ed38c7f6378cf0cedf408fd)

 #!/bin/sh

 set -e

 printf "Running autoconf...\n"

 autoconf -Wall --force

 printf "Done. You may now run:\n    ./configure\n"