panvk/ci: Increase panfrost-g52-vk fraction

premerge have a time limit of 15 min, those jobs takes between 20 to 33
min with a fraction of 8 right now.

Additionally, we only have 7 VIM3 and could be trying to queue 8 jobs.

Let's fraction to 32 for now and revert back to 2 runners.

Signed-off-by: Mary Guillemard <mary.guillemard@collabora.com>
Fixes: 2f54228da5 ("panvk/ci: Update to run full CTS on G52")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31404>

src/panfrost/ci/deqp-panfrost-g52-vk.toml

@@ -2,4 +2,4 @@
 deqp = "/deqp/external/vulkancts/modules/vulkan/deqp-vk"
 caselists = ["/deqp/mustpass/vk-main.txt"]
 renderer_check = "Mali-G52"
-fraction = 8
+fraction = 32

src/panfrost/ci/gitlab-ci.yml

@@ -331,7 +331,7 @@ panfrost-g52-gl:arm64:
     PAN_MESA_DEBUG: "deqp,sync,indirect"
 
 panfrost-g52-vk:arm64:
-  parallel: 4
+  parallel: 2
   extends:
     - .lava-test-deqp:arm64
     - .panfrost-test