ci/softpipe,llvmpipe: Disable Xvfb server reset on piglit runs.

The resets take time that we don't need to spend.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14904>

src/gallium/drivers/llvmpipe/ci/gitlab-ci.yml

@@ -34,7 +34,7 @@ llvmpipe-piglit-gl:
     LP_NUM_THREADS: 0
     PIGLIT_PROFILES: quick
   script:
-    - LD_LIBRARY_PATH=`pwd`/install xvfb-run install/piglit/piglit-runner.sh
+    - LD_LIBRARY_PATH=`pwd`/install xvfb-run --server-args='-noreset' install/piglit/piglit-runner.sh
 
 llvmpipe-traces:
   extends:

src/gallium/drivers/softpipe/ci/gitlab-ci.yml

@@ -43,4 +43,4 @@ softpipe-piglit:
   variables:
     PIGLIT_PROFILES: gpu
   script:
-    - LD_LIBRARY_PATH=`pwd`/install/lib xvfb-run install/piglit/piglit-runner.sh
+    - LD_LIBRARY_PATH=`pwd`/install/lib xvfb-run --server-args='-noreset' install/piglit/piglit-runner.sh