Vulkan: Simplify AppendToPNextChain use The function is turned into a template to avoid the reinterpret_cast at call sites. Additionally, uses Vulkan's own VkBaseOutStructure instead of a bespoke definition. Bug: angleproject:4027 Change-Id: Ib236d44a12c0363e7e89b9bf2ed5ab8166252730 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1924992 Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Tobin Ehlis <tobine@google.com>