fix memcpy declaration

sflphone-common/src/audio/audioloop.cpp

@@ -34,7 +34,7 @@
 
 #include "audioloop.h"
 #include <math.h>
-#include <strings.h>
+#include <cstring>
 
 AudioLoop::AudioLoop() :_buffer (0),  _size (0), _pos (0), _sampleRate (0)
 {

sflphone-common/src/audio/sound/tone.cpp

@@ -37,7 +37,7 @@
 #include "tone.h"
 #include <math.h>
 #include <cstdlib>
-#include <strings.h>
+#include <cstring>
 
 #define TABLE_LENGTH 4096
 double TWOPI = 2 * M_PI;