Ever since vk::destroy calls the object destructor, we can have std
objects in our vulkan objects, rather than std object pointers, which
allows us to allocate them using the provided allocator, rather than
having to use DEVICE_MEMORY.

I'm unsure whether there was an actual memory leak here or if ASAN
was detecting something that wasn't there, but this cl cleans up std
object allocation and fixes whatever ASAN was detecting. With this
change, the fuzzer run now completes without issue.

Bug: chromium:1107112
Change-Id: Ib78451639131eb518e2bf8d63ba70b930aba2216
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/48328
Presubmit-Ready: Alexis Hétu <sugoi@google.com>
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>