[clang] [clang] Split up `SemaDeclAttr.cpp` (PR #93966)

[Alexey Bader via cfe-commits]

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@@ -14,9 +14,11 @@
 #define LLVM_CLANG_SEMA_SEMASYCL_H
 
 #include "clang/AST/Decl.h"
+#include "clang/AST/DeclBase.h"
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bader wrote:

> This one should be fixed as well now.

Can we drop `#include "clang/AST/Decl.h"` as well?

https://github.com/llvm/llvm-project/pull/93966