upgrade to x/term instead of crypto/ssh/terminal

Simplify some of the password hashing logic. This requires a bump of irctest.

vendor/golang.org/x/sys/unix/syscall_bsd.go

@@ -245,8 +245,7 @@ func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
 				break
 			}
 		}
-		bytes := (*[len(pp.Path)]byte)(unsafe.Pointer(&pp.Path[0]))[0:n]
-		sa.Name = string(bytes)
+		sa.Name = string(unsafe.Slice((*byte)(unsafe.Pointer(&pp.Path[0])), n))
 		return sa, nil
 
 	case AF_INET: