[analyzer] Pointers escape into +[NSValue valueWithPointer:]...

...even though the argument is declared "const void *", because this is
just a way to pass pointers around as objects. (Though NSData is often
a better one.)

PR18262

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@198710 91177308-0d34-0410-b5e6-96231b3b80d8