[clang] [SYCL] Add sycl_external attribute (PR #140282)

[via cfe-commits]

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@@ -12746,6 +12746,11 @@ def err_sycl_special_type_num_init_method : Error<
   "types with 'sycl_special_class' attribute must have one and only one '__init' "
   "method defined">;
 
+//SYCL external attribute diagnostics
+def err_sycl_attribute_internal_decl
+    : Error<"%0 attribute cannot be applied to a %select{function|variable}1"
+            " without external linkage">;
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schittir wrote:

Planning to address this and add missing diagnostics in a subsequent PR. 

https://github.com/llvm/llvm-project/pull/140282