Add shims for include/gpu/d3d, gl, mock, and vk headers

The goal is to migrate clients to point into the include/gpu/ganesh
subfolders, now that we have Graphite also.

Change-Id: I7269acfae5c26518c2a61930a8af9584682751cd
Bug: b/40044159
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/892736
Reviewed-by: Robert Phillips <robertphillips@google.com>
Commit-Queue: Kaylee Lubick <kjlubick@google.com>
181 files changed