SpecializationInfo was default copy-constructed / assigned, and held a raw pointer to the copy of the VkSpecializationInfo. This struct was deleted in the destructor, trashing any other copies.

Fixes undefined behavior and crashes of a few Vulkan samples.

Bug b/123588002

Change-Id: I7adcec2d51bc357ef5bcee1ec6bdafe9ecd208a7
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/34454
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Tested-by: Ben Clayton <bclayton@google.com>