Fix testcases.

* tests/extrac08.at: Ensure a predictable umask value.
* tests/xform-h.at (xform): do not depend on file name
ordering.

tests/extrac08.at

@@ -34,6 +34,7 @@ AT_SETUP([restoring mode on existing directory])
 AT_KEYWORDS([extract extrac08])
 
 AT_TAR_CHECK([
+umask 000
 mkdir dir
 chmod 755 dir
 echo bla > dir/file

tests/xform-h.at

@@ -32,7 +32,7 @@ AT_KEYWORDS([transform xform xform-h])
 
 m4_define([xform],[
 echo "$1"
-tar cf archive --transform="s,^basedir/,,$2" basedir
+tar cf archive --transform="s,^basedir/,,$2" basedir/test basedir/test_link
 tar tvf archive | sed -n 's/.*test_link link to //p'
 ])