source: Fix extract in git sources
source: Fix extract in git sources

Use os.makedirs which can create several path levels at once, instead of
failing.
For instance Cmake sources are extracted to ARCH/PACKAGE-VERSION/_builddir/
and two directories have to be created.
All other source types are already using os.makedirs.

Part-of: <https://gitlab.freedesktop.org/gstreamer/cerbero/-/merge_requests/700>

nirbheek/cerbero,nirbheek/cerbero,nirbheek/cerbero,nirbheek/cerbero