set src-dir as parameter in docker_generate_package script

Change-Id: I82eaec94c312b4fc3d46bfdf7ba8f94e8dc7f900
Merge commit 'refs/changes/59/3159/2' of ssh://gerrit.tuleap.net:29418/tuleap into HEAD

* ssh://gerrit.tuleap.net:29418/tuleap:
  set src-dir as parameter in docker_generate_package script

Change-Id: I5e990c31d5def1312f0879b4de39028d7cd3543c
This is Tuleap 7.6.99.12

Change-Id: I191133f75efb7d48a4878603fdb55a928cb056d3