[ET-VK] Fix debug build + print maximum storage buffer size with device limits

## Context

Two simple fixes/improvements.

1. Recently the interface to retrieve a `VkPipeline` from a pipeline cache was updated. Some code hidden behind debug compile flags was not updated. Updating the call site fixes building Vulkan with `etvk.debug = 1`.
2. Print the maximum storage buffer size when printing out the physical device limits. This is useful information to have.

Differential Revision: [D70718388](https://our.internmc.facebook.com/intern/diff/D70718388/)

ghstack-source-id: 270150972
Pull Request resolved: https://github.com/pytorch/executorch/pull/9016

Co-authored-by: Stephen Jia <ssjia@meta.com>