abuild: fix git_* functions

Add -- to explicitly separate out the file path.

Let git_last_commit_epoch take an option with the hash.

abuild.in

@@ -859,17 +859,17 @@ prepare_language_packs() {
 
 # echo '-dirty' if git is not clean
 git_dirty() {
-	[ $($git status -s "$startdir" | wc -l) -ne 0 ] && echo "-dirty"
+	[ $($git status -s -- "$startdir" | wc -l) -ne 0 ] && echo "-dirty"
 }
 
 # echo last commit hash id
 git_last_commit() {
-	$git log --format=oneline -n 1 "$startdir" | awk '{print $1}'
+	$git log --format=oneline -n 1 -- "$startdir" | awk '{print $1}'
 }
 
 # date of last commit
 git_last_commit_epoch() {
-	$git log -1 --format=%cd --date=unix -- "$startdir"
+	$git log -1 --format=%cd --date=unix $1 -- "$startdir"
 }
 
 get_maintainer() {