[clang] [HLSL] Add ByteAddressBuffer definition to HLSLExternalSemaSource #113477 (PR #116699)

[Helena Kotas via cfe-commits]

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@@ -0,0 +1,49 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library -x hlsl -ast-dump -DEMPTY \
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hekota wrote:

Since the test now covers multiple buffers please rename it to ByteAddressBuffer**s**-AST.hlsl and update the PR title and description.

https://github.com/llvm/llvm-project/pull/116699