libxml2: Reformat runtest.patch

Reformatted runtest.patch to allow it to be applied using git am.
This makes it easier to apply the series of patches to the original git repo.

There are no changes to the code of the patch other than the reformat.

Previously, the patch claimed to be a backport, but I have not found an
upstream commit so I've changed the Upstream-Status to pending.

Signed-off-by: Tony Tascioglu <tony.tascioglu@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>