Corrected system time check function return values

Author: Mika Leppänen

source/6LoWPAN/ws/ws_pae_auth.c

@@ -935,11 +935,11 @@ static uint32_t ws_pae_auth_lifetime_system_time_check(pae_auth_t *pae_auth, int
     if (pae_auth->system_time_diff > TIME_DIFFERENCE_THRESHOLD + seconds + dec_extra_seconds) {
         time_diff = pae_auth->system_time_diff - seconds - dec_extra_seconds;
     } else {
-        return 0;
+        return dec_extra_seconds;
     }
     pae_auth->system_time_diff = 0;
 
-    uint32_t new_dec_extra_seconds = 0;
+    uint32_t new_dec_extra_seconds = dec_extra_seconds;
 
     if (time_diff > 0) {
         /* If the system time has made a large jump then use the stored time to calculate the lifetime