[clang] [clang][SYCL Upstreaming] Add sycl_external attribute and restrict emitting device code (PR #140282)

[Mariya Podchishchaeva via cfe-commits]

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@@ -1,128 +1,128 @@
 // RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -fsycl-is-device -disable-llvm-passes -emit-llvm %s -o - | FileCheck %s
 void bar(int &Data) {}
-// CHECK: define dso_local void @[[RAW_REF:[a-zA-Z0-9_]+]](ptr noundef nonnull align 4 dereferenceable(4) %
+// CHECK-DAG: define {{.*}} void @[[RAW_REF:[a-zA-Z0-9_]+]](ptr noundef nonnull align 4 dereferenceable(4) %
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Fznamznon wrote:

We could actually check the calling convention and linkage instead of simply skipping it.

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