git-version-gen: revert to same version as libosmocore

OpenBSC required additional care because of an unusal .git location.
This is not need anymore for osmo-mgw

Change-Id: I5aad67612026947ad52cdc9477b603732c146e7a

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]*) ;;