[WIP] Add option to build with all xnnpack, vulkan, qnn#16189

Copilot wants to merge 1 commit intomainpytorch/executorch:mainfrom

copilot/add-build-option-xnnpack-vulkan-qnnpytorch/executorch:copilot/add-build-option-xnnpack-vulkan-qnnCopy head branch name to clipboard