vala: refresh patch

vala: refresh patch

Refresh the following patch:
"disable-graphviz.patch" to fix this warning:

Some of the context lines in patches were ignored. This can lead to
incorrectly applied patches.
The context lines in the patches can be updated with devtool:

    devtool modify <recipe>
    devtool finish --force-patch-refresh <recipe> <layer_path>

Then the updated patches and the source tree (in devtool's workspace)
should be reviewed to make sure the patches apply in the correct place
and don't introduce duplicate lines (which can, and does happen
when some of the context is ignored). Further information:
http://lists.openembedded.org/pipermail/openembedded-core/2018-March/148675.html
https://bugzilla.yoctoproject.org/show_bug.cgi?id=10450
Details:
        checking file configure.ac
        checking file libvaladoc/Makefile.am
        checking file libvaladoc/html/basicdoclet.vala
        checking file libvaladoc/html/htmlmarkupwriter.vala
        Hunk #1 succeeded at 51 with fuzz 1 (offset 8 lines).

Signed-off-by: Maxin B. John <maxin.john@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>