Add support for setting the peer verify name via the QNetwork* classes

This adds functions to QNetworkRequest to be able to set the
peerVerifyName. An overload of connectToHostEncrypted is also added to
have an extra argument to allow setting it directly in this manner too.

Fixes: QTBUG-73125
Change-Id: I371e90035b53a74c9eb3cef64f367e307dce073e
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>