Fix up some more non-prototyped declarations with swift_names.

This is now diagnosed on the Clang side.

Author: jckarter

test/IDE/Inputs/custom-modules/ImportAsMemberError.h

@@ -19,15 +19,13 @@ typedef NSObject<ImportedProtocolBase> *ImportedProtocolBase_t;
 typedef NSObject<ErrorProto> *ErrorProto_t;
 
 // Instance and static member onto protocol
-void mutateSomeStaticState()
+void mutateSomeStaticState(void)
     __attribute__((swift_name("ErrorProto.mutateSomeStaticState()"))); // ok
 void mutateSomeInstanceState(ErrorProto_t self) __attribute__((
     swift_name("ErrorProto.mutateSomeInstanceState(self:)"))); // error
 
 // Non-prototype declaration
 extern void IAMErrorStructHasPrototype(void)
     __attribute__((swift_name("ErrorStruct.hasPrototype()"))); // ok
-extern void IAMErrorStructNonPrototype()
-    __attribute__((swift_name("ErrorStruct.nonPrototype()"))); // error
 
 #endif // IMPORT_AS_MEMBER_ERR_H

test/IDE/import_as_member_objc.swift

@@ -43,8 +43,6 @@ import IAMError
 
 // Errors
 ErrorStruct.hasPrototype();
-ErrorStruct.nonPrototype();
-  // expected-error@-1{{type 'ErrorStruct' has no member 'nonPrototype'}}
 
 // Protocols
 @objc class Foo : NSObject, IAMProto {}