Change test_2038 routine to return error on time_t size==4

Seems ctime might be seg faulting on the test
https://github.com/Hamlib/Hamlib/issues/1492

src/misc.c

@@ -3048,6 +3048,13 @@ int rig_test_2038(RIG *rig)
     time_t x;
 
     rig_debug(RIG_DEBUG_TRACE, "%s: enter\n", __func__);
+
+    if (sizeof(time_t) == 4)
+    {
+        rig_debug(RIG_DEBUG_TRACE, "%s: ctime is null, 2038 test failed\n", __func__);
+        return 0;
+    }
+
     x = (time_t)((1U << 31) - 1);
     char *s = ctime(&x);
 
@@ -3056,6 +3063,7 @@ int rig_test_2038(RIG *rig)
         rig_debug(RIG_DEBUG_TRACE, "%s: ctime is null, 2038 test failed\n", __func__);
         return 1;
     }
+
     if (!strstr(s, "2038")) { return 1; }
 
     x += 1;