virgl/driconf: Add tweak to emulated coherent buffer writes

This tweak makes it possible to enable the emulation of coherent
buffer writes with virgl.

Signed-off-by: Gert Wollny <gert.wollny@collabora.com>
40 jobs for !2066 with virgl-tweak-emu-coherent-write in 14 minutes and 26 seconds (queued for 4 seconds)
latest detached
Status Job ID Name Coverage
  Containers
passed #641408
debian-10

00:00:19

passed #641409
debian-9

00:00:20

passed #641410
aarch64
test-container:arm64

00:00:21

 
  Build
passed #641413
meson-arm64

00:05:19

passed #641412
meson-armhf

00:03:15

passed #641415
meson-clang

00:07:26

passed #641418
meson-clover

00:05:29

passed #641419
meson-clover-old-llvm

00:05:46

passed #641421
meson-i386

00:02:58

passed #641411
meson-main

00:09:32

passed #641414
meson-swr-glvnd

00:05:20

passed #641420
meson-vulkan

00:01:43

passed #641422
scons

00:09:02

passed #641423
scons-old-llvm

00:07:54

passed #641416
scons-swr

00:07:52

passed #641417
scons-win64

00:06:57

 
  Test
passed #641444
db410c
arm64_a306_gles2 1/4

00:04:09

passed #641445
db410c
arm64_a306_gles2 2/4

00:05:58

passed #641446
db410c
arm64_a306_gles2 3/4

00:04:07

passed #641447
db410c
arm64_a306_gles2 4/4

00:04:30

passed #641433
mesa-cheza
arm64_a630_gles2

00:04:51

passed #641434
mesa-cheza
arm64_a630_gles31 1/4

00:06:16

passed #641435
mesa-cheza
arm64_a630_gles31 2/4

00:07:32

passed #641436
mesa-cheza
arm64_a630_gles31 3/4

00:07:30

passed #641437
mesa-cheza
arm64_a630_gles31 4/4

00:07:38

passed #641438
mesa-cheza
arm64_a630_gles3 1/6

00:05:08

passed #641439
mesa-cheza
arm64_a630_gles3 2/6

00:04:03

passed #641440
mesa-cheza
arm64_a630_gles3 3/6

00:03:52

passed #641441
mesa-cheza
arm64_a630_gles3 4/6

00:04:57

passed #641442
mesa-cheza
arm64_a630_gles3 5/6

00:04:12

passed #641443
mesa-cheza
arm64_a630_gles3 6/6

00:04:49

passed #641424
test-llvmpipe-gles2 1/4

00:02:21

passed #641425
test-llvmpipe-gles2 2/4

00:02:30

passed #641426
test-llvmpipe-gles2 3/4

00:03:05

passed #641427
test-llvmpipe-gles2 4/4

00:03:16

passed #641428
test-softpipe-gles2 1/4

00:01:23

passed #641429
test-softpipe-gles2 2/4

00:01:27

passed #641430
test-softpipe-gles2 3/4

00:01:31

passed #641431
test-softpipe-gles2 4/4

00:01:31

passed #641432
test-softpipe-gles3-limited

00:03:43