drm/amdgpu: bump version for invalidate L2 before SDMA IBs

This fixes GPU hangs due to cache coherency issues.
Bump the driver version. Split out from the original patch.

Signed-off-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Tested-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>