media-libs/virglrenderer: version bump to 0.6.0

media-libs/virglrenderer: version bump to 0.6.0

This is a hand-packaged version of upstream commit

  737c3350850ca4dbc5633b3bdb4118176ce59920

(version 0.6.0 with two additional security patches)
containing fixes for the following security issues:

CVE-2016-10163, bug #606996
CVE-2017-5580,  bug #607022
CVE-2016-10214, bug #608734
CVE-2017-5957,  bug #609400
CVE-2017-5956,  bug #609402
CVE-2017-5993,  bug #609492
CVE-2017-5994,  bug #609494
CVE-2017-6210,  bug #610678
CVE-2017-6209,  bug #610680
CVE-2017-6386,  bug #611378
CVE-2017-6355,  bug #611380
CVE-2017-6317,  bug #611382

Package-Manager: Portage-2.3.5, Repoman-2.3.2