Reverts previous commit for min dtmf duration.

src/org/jitsi/impl/neomedia/transform/dtmf/DtmfTransformEngine.java

@@ -371,14 +371,6 @@ else if(toneTransmissionState
             }
         }
 
-        // skip packets before reaching minimal duration
-        if(minimalToneDuration != -1
-            && currentDuration < minimalToneDuration)
-        {
-            // do not send packets
-            return null;
-        }
-
         dtmfPkt.init(
             toneCode,
             pktEnd,