[vulkan] glsl shaders relaxed precision mode to cmake option (#43076)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/43076
Test Plan: Imported from OSS
Reviewed By: AshkanAliabadi
Differential Revision: D23143354
Pulled By: IvanKobzarev
fbshipit-source-id: 7b3ead1e63cf8acf6e8e547080a8ead7a2db994b
