Prevent spurious SSL errors from local certificates.

Qt since approximately 4.4 has set the verify callback on both the SSL
store and the SSL context. Only the latter is actually needed. This is
normally not a problem, but openssl prior to 1.0.2 uses the verify
code to find the intermediate certificates for any local certificate
that has been set which can lead to verification errors for the local
certificate to be emitted.

Task-number: QTBUG-33228
Task-number: QTBUG-7200
Task-number: QTBUG-24234
Change-Id: Ie4115e7f7faa1267ea9b807c01b1ed6604c4a16c
Reviewed-by: Peter Hartmann <phartmann@blackberry.com>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>