ObjC Class Property: diagnostics when accessing a class property using instance.

When a class property is accessed with an object instance, before this commit,
we try to apply a typo correction of the same property:
property 'c' not found on object of type 'A *'; did you mean 'c'?

With this commit, we correctly emit a diagnostics:
property 'c' is a class property; did you mean to access it with class 'A'?

rdar://26866973

llvm-svn: 274076