In order to properly generate org-version.el, the current build in 
mk/targets.mk requires a query of the repo's tags. Shallow clones 
do not have tags and so org-version will be generated as "N/A". In 
the attached patch, support for generating org-version.el from 
shallow clones is added. It is done by querying the upstream 
remote via git ls-remote and parsing the output. In this case, a 
more well formed org-version string will be generated. However, it 
will be missing the "commits since last tag" information. e.g.

"release_9.6.1-n/a-gabc123"