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: I9d895fa90991d47e9626a8e7fa701540b658194c

git-version-gen

@@ -92,8 +92,8 @@ fi
 if test -n "$v"
 then
     : # use $v
-elif test -d ./.git \
-    && v=`git describe --abbrev=4 --match='v*' HEAD 2>/dev/null \
+elif
+       v=`git describe --abbrev=4 --match='v*' HEAD 2>/dev/null \
 	  || git describe --abbrev=4 HEAD 2>/dev/null` \
     && case $v in
 	 [0-9]*) ;;