RingAccount: fix uninitialized class members

Set true as default value to members:
allowPeersFromHistory_
allowPeersFromContact_
allowPeersFromTrusted_

Coverity CID # 1369576

Change-Id: I38499608ee35692e96c511f08d261eea8ad9b72b
Tuleap: #909

src/ringdht/ringaccount.h

@@ -389,9 +389,10 @@ class RingAccount : public SIPAccountBase {
         std::shared_future<tls::DhParams> dhParams_;
         std::mutex dhParamsMtx_;
         std::condition_variable dhParamsCv_;
-        bool allowPeersFromHistory_;
-        bool allowPeersFromContact_;
-        bool allowPeersFromTrusted_;
+
+        bool allowPeersFromHistory_ {true};
+        bool allowPeersFromContact_ {true};
+        bool allowPeersFromTrusted_ {true};
 
         /**
          * Optional: "received" parameter from VIA header