ci: remove LAVA prefix from variables which can be used also elsewhere

At least these two can be easily used in bare-metal or Labgrid setups.

Currently I already have MR for implementing these for Labgrid.

Reviewed-by: Guilherme Gallo <guilherme.gallo@collabora.com>
Signed-off-by: David Heidelberg <david.heidelberg@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24665>

.gitlab-ci/test-source-dep.yml

@@ -97,7 +97,7 @@
   extends:
     - .performance-rules
   variables:
-    LAVA_JOB_PRIORITY: 40
+    JOB_PRIORITY: 40
     PIGLIT_REPLAY_SUBCOMMAND: "profile"
     PIGLIT_REPLAY_EXTRA_ARGS: "--db-path ${CI_PROJECT_DIR}/replayer-db/"
     # More than this can hit OOM due to BOs leaked during the replay of the last frame
@@ -105,7 +105,7 @@
     # We don't want for more than one workload to be submitted to the GPU at a time
     FDO_CI_CONCURRENT: 1
     # Piglit is very sparse in its status output and downloads of big traces can take a while
-    LAVA_DEVICE_HANGING_TIMEOUT_SEC: 600
+    DEVICE_HANGING_TIMEOUT_SEC: 600
     GIT_STRATEGY: none
     HWCI_FREQ_MAX: "true"
     # Always use the same device