srogue: more compatibility improvements.

Randomness now uses mdport, and xcrypt.c has been replaced with the
rogue5 version.

Super-Rogue now builds on MinGW.

srogue/mdport.c

@@ -1567,3 +1567,27 @@ md_resetpriv(void)
 	setgid(playgid);
 #endif
 }
+
+int
+md_random(void)
+{
+#if defined (HAVE_LRAND48)
+	return lrand48();
+#elif defined (HAVE_RANDOM)
+	return random();
+#else
+	return rand();
+#endif
+}
+
+void
+md_srandom(unsigned int seed)
+{
+#if defined (HAVE_SRAND48)
+	srand48(seed);
+#elif defined (HAVE_SRANDOM)
+	srandom(seed);
+#else
+	srand(seed);
+#endif
+}