ntp+refclock: add functions to modify offset option

stubs.c

@@ -320,6 +320,12 @@ NSR_ModifyMinstratum(IPAddr *address, int new_min_stratum)
   return 0;
 }
 
+int
+NSR_ModifyOffset(IPAddr *address, double new_offset)
+{
+  return 0;
+}
+
 int
 NSR_ModifyPolltarget(IPAddr *address, int new_poll_target)
 {
@@ -419,6 +425,12 @@ RCL_ReportSource(RPT_SourceReport *report, struct timespec *now)
   memset(report, 0, sizeof (*report));
 }
 
+int
+RCL_ModifyOffset(uint32_t ref_id, double offset)
+{
+  return 0;
+}
+
 #endif /* !FEAT_REFCLOCK */
 
 #ifndef FEAT_SIGND