[Mesa-stable] vc4 commits for 12.0 stable

[Eric Anholt]

Series of fixes for 12.0 for vc4.  There's one trivial conflict,
so I put the whole series up at:

https://github.com/anholt/mesa/tree/12.0

commit 067c5b10b690b949ac28c4aea237f398f8251fff
Author: Rob Herring <robh at kernel.org>
Date:   Tue Jun 14 16:17:44 2016 -0500

    vc4: fix vc4_resource_from_handle() stride calculation

commit c65a00eaff85160dd556856c8c2eecf3aabdc4d5
Author: Eric Anholt <eric at anholt.net>
Date:   Mon Jul 11 16:46:20 2016 -0700

    vc4: Close our screen's fd on screen close.

commit ce8504d196291452b42ed755ed3830ecb16febcd
Author: Eric Anholt <eric at anholt.net>
Date:   Tue Jul 19 11:10:36 2016 -0700

    vc4: Disable early Z with computed depth.

commit a0671d67def9e83ae511f758091b87d4ac34bea4
Author: Eric Anholt <eric at anholt.net>
Date:   Tue Aug 2 11:02:21 2016 -0700

    vc4: Fix a leak of the src[] array of VPM reads in optimization.

commit 9ace2c13550609dfe78164f104500d438821f383
Author: Rob Herring <robh at kernel.org>
Date:   Fri Jul 22 15:28:30 2016 -0500

    vc4: add hash table look-up for exported dmabufs

commit 9f956909591fb259ce01f1882c3367978e8ec2fb
Author: Eric Anholt <eric at anholt.net>
Date:   Tue Aug 2 10:57:01 2016 -0700

    vc4: Fix leak of the bo_handles table.

<#secure method=pgpmime mode=sign>