[yocto] Removing old git revisions from the build

[Andy Ng]

Hello,

I am using Dylan and my kernel recipe has AUTOREV.
Everything works fine and any new kernel changes are checked out and
a new kernel is built. However, I have noticed that the old builds are
not deleted and after a while started having space problems.

Is there any way to have the old git revisions deleted automatically
from the "tmp" area?

Best regards
Andy