[clang] [Clang] Minimal support for availability attributes on partial specializations (PR #138426)

[Shafik Yaghmour via cfe-commits]

================
@@ -72,3 +72,58 @@ template <class B1> struct B {
 
 template struct B<A>; // expected-note {{requested here}}
 } // namespace GH58547
+
+
+namespace GH44496 {
+  template <class> struct my_template {
----------------
shafik wrote:

```suggestion
template <class> struct my_template {
```

https://github.com/llvm/llvm-project/pull/138426