cherokee: only install configured.py once

Both the two rules install-adminpyDATA and install-generatedDATA will
install the configured.py to the same location, they can run parallel,
and they use "install -m", which would might build failures:

/usr/bin/install: setting permissions for `/path/to/configured.py': No such file or directory

This is because the first install is setting the permission while the
second install is removing the file an re-install.

Only install the configured.py once will fix the problem, I think that
there is no side effect since it installed the same file to the same
location twice in the past.

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>