Compile LSTM::PrintW and LSTM::PrintDW conditionally

Signed-off-by: Stefan Weil <sw@weilnetz.de>

src/lstm/lstm.cpp

@@ -772,6 +772,8 @@ void LSTM::CountAlternators(const Network &other, TFloat *same, TFloat *changed)
   }
 }
 
+#if DEBUG_DETAIL > 3
+
 // Prints the weights for debug purposes.
 void LSTM::PrintW() {
   tprintf("Weight state:%s\n", name_.c_str());
@@ -834,6 +836,8 @@ void LSTM::PrintDW() {
   }
 }
 
+#endif
+
 // Resizes forward data to cope with an input image of the given width.
 void LSTM::ResizeForward(const NetworkIO &input) {
   int rounded_inputs = gate_weights_[CI].RoundInputs(na_);