Revert "docs/relnotes/19.3: fix vulkan version reported"
This reverts commit 5ff443b8
I made a mistake, VK 1.2 happened after Mesa 19.3
(can be checked by looking at src/intel/vulkan/anv_extensions.py for instance)
The script & 20.0 changes of !4092 (merged) were correct though
/cc @dbaker