[clang] [SPIR-V] Permit implicit conversion to generic AS (PR #175109)

[Matt Arsenault via cfe-commits]

================
@@ -317,6 +318,16 @@ class LLVM_LIBRARY_VISIBILITY BaseSPIRVTargetInfo : public BaseSPIRTargetInfo {
     return Feature == "spirv";
   }
 
+  virtual bool isAddressSpaceSupersetOf(LangAS A, LangAS B) const override {
+    // The geneirc space AS(4) is a superset of all the other address
----------------
arsenm wrote:

```suggestion
    // The generic space AS(4) is a superset of all the other address
```

https://github.com/llvm/llvm-project/pull/175109