ar_energy: reduced zeroCrossingCount magnitude by 1/3

zero crossing counter is often larger than in the prototype by @troyhacks - due to calculation after filtering (catches more crossings), and due to the fixed condition for detecting zero crossings (doubles the number of crossings).

This patch reduces the final value to 2/3, so it typically stays below 256.

usermods/audioreactive/audio_reactive.h

@@ -563,6 +563,7 @@ void FFTcode(void * parameter)
         }
       }
     }
+    newZeroCrossingCount = (newZeroCrossingCount*2)/3; // reduce value so it typicially stays below 256
     zeroCrossingCount = newZeroCrossingCount; // update only once, to avoid that effects pick up an intermediate value
 
     // release highest sample to volume reactive effects early - not strictly necessary here - could also be done at the end of the function