[Vulkan] Replace Conv2dOpContext by VulkanOpContext (#78818)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/78818
ghstack-source-id: 158143558
Reviewed By: SS-JIA
Differential Revision: D36674287
fbshipit-source-id: e6b5886468ea405d150aeaf117e4072a52e1bab2
