[SIL][PackageCMO] Allow optimizing [serialized_for_pkg] functions during SIL

inlining, generic/closure specialization, and devirtualization optimization passes.

SILFunction::canBeInlinedIntoCaller now exlicitly requires a caller's SerializedKind_t arg.
isAnySerialized() is added as a convenience function that checks if [serialized] or [serialized_for_pkg].

Resolves rdar://128704752

include/swift/SIL/SILProperty.h

@@ -53,7 +53,10 @@ public:
                              AbstractStorageDecl *Decl,
                              std::optional<KeyPathPatternComponent> Component);
 
-  bool isNotSerialized() const { return SerializedKind_t(Serialized) == IsNotSerialized; }
+  bool isAnySerialized() const {
+    return SerializedKind_t(Serialized) == IsSerialized ||
+           SerializedKind_t(Serialized) == IsSerializedForPackage;
+  }
   SerializedKind_t getSerializedKind() const {
     return SerializedKind_t(Serialized);
   }