Ethernet: remove SSID_MAX_LENGTH define

Author: pennam

libraries/Ethernet/src/Ethernet.cpp

@@ -1,7 +1,5 @@
 #include "Ethernet.h"
 
-#define SSID_MAX_LENGTH 32
-
 int arduino::EthernetClass::begin(uint8_t *mac, unsigned long timeout, unsigned long responseTimeout) {
   if (eth_if == nullptr) {
     return 0;