[clang] [clang] Factor out OpenACC part of `Sema` (PR #84184)

[Aaron Ballman via cfe-commits]

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@@ -1162,6 +1162,11 @@ class Sema final {
   /// CurContext - This is the current declaration context of parsing.
   DeclContext *CurContext;
 
+  SemaOpenACC &OpenACC() {
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AaronBallman wrote:

I think @sam-mccall is reading the coding guidelines the same way I read them, and I agree with his conclusion that I also prefer `openACC()` over `getOpenACC()`. I don't find `get` to add much value to readability in this case and I think deviating from the style guideline is appropriate.

https://github.com/llvm/llvm-project/pull/84184