cc/gcc: add host parameter to core compiler build process

Tell the core compiler what host it should run on (instead of
hard-coding runing on CT_HOST).

No functional change so far, switching between CT_HOST and CT_BUILD
will come in a following patch.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

 #!/bin/sh

 set -e

 printf "Running autoconf...\n"

 autoconf -Wall --force

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