vk_pipeline_cache: Skip compute pipelines on Intel proprietary drivers

Intel's SPIR-V shader compiler is broken. For now, skip compiling any compute pipelines until they fix this issue.
This is not a perfect workaround, as there are a small subset of non-compute pipelines that still cause it to crash, but this should cover the majority of crashes.
It is unfortunate that even with a test case reported 6 months ago the issue has not been fixed in favor of fixing "the most popular games and apps".
Intel, you can do better than this.