Updates to volk, vulkan headers, `vk_enum_string_helper.h`, VMA,
glslang, spirv-reflect.
VMA doesn't tag SDK releases specifically, and still hasn't had a tagged
release since 3.0.1, but the Vulkan SDK now seems to ship a recent master
commit, so we do the same.
This updates VMA and instead of using the custom small pool approach from 4e6c9d3ae9, lazily creates pools for the relevant memory type indices, which doesn't require patching VMA.
Also, patches already merged upstream or not needed any longer are removed.
