add option -patch1 to ci-build script

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14939 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
tools/ci-build: add possibility of changing directory on unix-like architectures

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14940 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02