C++: Disable "Replace Dot for Arrow" auto-correction for ObjC sources

In the light of Obj-C properties this seems to annoy more than to help.

Change-Id: I48f92d505035369f48e8798d0972ef00306bdde0
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>