sim65 cycles 32-bit range fix

long is 64-bit on some platforms, making this inconsistent, added range check to catch overflow.
reduced tests requesting 5 billion cycles to 2^32-1 so they can fun on 32-bit long sim65.

src/sim65/main.c

@@ -36,6 +36,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
+#include <limits.h>
 
 /* common */
 #include "abend.h"
@@ -140,6 +141,10 @@ static void OptQuitXIns (const char* Opt attribute ((unused)),
 /* quit after MaxCycles cycles */
 {
     MaxCycles = strtoul(Arg, NULL, 0);
+    /* Guard against overflow. */
+    if (MaxCycles == ULONG_MAX && errno == ERANGE) {
+        Error("'-x parameter out of range. Max: %lu",ULONG_MAX);
+    }
 }
 
 static unsigned char ReadProgramFile (void)