Changed every memcpy to SCA equivalent mbedtls_platform_memcpy

This makes physical attacks more difficult.
diff --git a/library/net_sockets.c b/library/net_sockets.c
index 76b0ecd..8e5abe2 100644
--- a/library/net_sockets.c
+++ b/library/net_sockets.c
@@ -408,7 +408,7 @@
             if( buf_size < *ip_len )
                 return( MBEDTLS_ERR_NET_BUFFER_TOO_SMALL );
 
-            memcpy( client_ip, &addr4->sin_addr.s_addr, *ip_len );
+            mbedtls_platform_memcpy( client_ip, &addr4->sin_addr.s_addr, *ip_len );
         }
         else
         {
@@ -418,7 +418,7 @@
             if( buf_size < *ip_len )
                 return( MBEDTLS_ERR_NET_BUFFER_TOO_SMALL );
 
-            memcpy( client_ip, &addr6->sin6_addr.s6_addr, *ip_len);
+            mbedtls_platform_memcpy( client_ip, &addr6->sin6_addr.s6_addr, *ip_len);
         }
     }