git-version-gen: Don't check for .git directory

This check is not in all our repos that use git-version-gen. Indeed it
seems to be a leftover of openbsc where I think it wanted to ensure
being called in the openbsc subfolder or something? libosmocore e.g.
doesn't have it.

In any case .git being a directory is not always true (if using git
worktree) so remove this check.

Change-Id: I4385cc4fb87ca4354a3c608a18aa3d2eb03a744f
1 file changed