recipetool: ensure git clone is standalone when extracting
If -x is specified and the specified URI was a git repository, we need
to ensure that the resulting clone is a sandalone and not one that has
pointers into the temporary fetch location or DL_DIR (since the git
fetcher does a local clone with -s). Split out the code from devtool
that already does this for "devtool modify -x" and reuse that.
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
