Don't mis-match method calls as member accesses

Two rules matched both $a->foo and $a->foo(), but they were apparently intended to only match the former.

Compare:

```
$foo = $this->getRequest();
$foo = $this->request;
```

"getRequest" should have a scope of "meta.function-call.php", "request" should have "variable.other.property.php". Before this patch, both get the latter. I don't understand how this works well enough, but it seems that the two rules that I modified here matched first and superseded the correct ones.