socket ID returned from socket(AF_INET, ....) in ESP32 does not start at 0

This check was in there because we used to keep track of which sockets had TLS with bits inside a 32 bit integer (using BITFIELD_SET). I'm pretty sure that's all been removed now we pass socketType through, so these checks could be taken out? I don't believe there's any reason to restrict the value of the socket handle at all now.