[clang] [HLSL] Allow narrowing in initialization lists (PR #108035)

[Cooper Partin via cfe-commits]

https://github.com/coopp approved this pull request.

looks fine.  Curious, why is this extra RUN: line added?  Doesn't the other one already contain the same parameters `-ast-dump -o - %s | FileCheck %s` ?

RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-compute -ast-dump -o - %s | FileCheck %s

https://github.com/llvm/llvm-project/pull/108035