MT#55283 fix unsigned integer underflow

The packet timestamp might be larger than our own "now" timestamp

Change-Id: I891dc1b6d191689980cce8e285c8f519f990c35d

daemon/call.c

@@ -245,7 +245,7 @@ no_sfd:
 			tmp_t_reason = OFFER_TIMEOUT;
 		}
 
-		if (rtpe_now.tv_sec - timestamp < check)
+		if (timestamp < rtpe_now.tv_sec || rtpe_now.tv_sec - timestamp < check)
 			good = true;
 
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