Refactor EGD conditional support

As per Jeremy's request in #124
Windows does not define HAVE_RAND_EGD resulting in the same conditional
support for EGD.

lib/krb5/crypto-rand.c

@@ -67,7 +67,7 @@ seed_something(void)
     /* Calling RAND_status() will try to use /dev/urandom if it exists so
        we do not have to deal with it. */
     if (RAND_status() != 1) {
-#if !defined(NO_RAND_EGD_METHOD) && defined(HAVE_RAND_EGD)
+#if defined(HAVE_RAND_EGD)
 	krb5_context context;
 	const char *p;