build-setup.sh: prevent git clone when only building container

When someone wants to just build the container, there's no need to clone
openbmc.

Tested:
- Confirmed no clone when CONTAINER_ONLY set to true
- Confirmed a clone when CONTAINER_ONLY is not set

Change-Id: I7765c8511cffe2db9b94f3e8e5815300fd9c65f1
Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
1 file changed