rootbld: run mkusers inside the chroot and don't affect host users

abuild.in

@@ -2362,7 +2362,7 @@ rootbld_actions() {
 	if ! want_check; then
 		_check=true
 	fi
-	for part in symlinksrc unpack prepare build $_check rootpkg; do
+	for part in symlinksrc unpack prepare mkusers build $_check rootpkg; do
 		runpart $part
 	done
 }
@@ -2395,8 +2395,6 @@ rootbld() {
 
 	msg "Preparing build chroot..."
 
-	mkusers
-
 	BUILD_ROOT=$(mktemp -d /var/tmp/abuild.XXXXXXXXXX)
 
 	mkdir -p "$BUILD_ROOT/proc" "$BUILD_ROOT/etc/apk/keys" \