[clang-tools-extra] [clang-tidy] Add documentation and smoke test for CUDA (PR #173699)

[Carlos Galvez via cfe-commits]

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@@ -0,0 +1,16 @@
+// RUN: clang-tidy %s -checks='-*,modernize-use-nullptr' -- \
+// RUN:   --cuda-path=%S/Inputs/CUDA \
+// RUN:   -nocudalib -nocudainc -I %S/Inputs/CUDA \
+// RUN:   --cuda-host-only | FileCheck %s
+// RUN: clang-tidy %s -checks='-*,modernize-use-nullptr' -- \
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carlosgalvezp wrote:

I think it's fine to just do one run of clang-tidy which goes through both host and device, instead of separating them (I see no benefit).

https://github.com/llvm/llvm-project/pull/173699