e1_input: enable tcp keepalive by default

Set the keepalive parameters to E1INP_USE_DEFAULT initially instead
of 0. Do this independent of the driver (the only driver making use of
this is ipaccess).

Closes: OS#5785
Change-Id: Ia7659c209aea0d26eb37d31e771adc91b17ae668
diff --git a/src/e1_input.c b/src/e1_input.c
index 6507835..ee529cc 100644
--- a/src/e1_input.c
+++ b/src/e1_input.c
@@ -506,6 +506,10 @@
 	line->num = e1_nr;
 	line->pcap_fd = -1;
 
+	line->keepalive_idle_timeout = E1INP_USE_DEFAULT;
+	line->keepalive_num_probes = E1INP_USE_DEFAULT;
+	line->keepalive_probe_interval = E1INP_USE_DEFAULT;
+
 	line->rate_ctr = rate_ctr_group_alloc(line, &e1inp_ctr_g_d, line->num);
 	if (!line->rate_ctr) {
 		LOGPIL(line, DLINP, LOGL_ERROR, "Cannot allocate counter group\n");
diff --git a/src/e1_input_vty.c b/src/e1_input_vty.c
index af30ed9..f6781d1 100644
--- a/src/e1_input_vty.c
+++ b/src/e1_input_vty.c
@@ -379,12 +379,9 @@
 		if (!line->keepalive_num_probes)
 			vty_out(vty, " no e1_line %u keepalive%s", line->num,
 				VTY_NEWLINE);
-		else if (line->keepalive_idle_timeout == E1INP_USE_DEFAULT &&
-			 line->keepalive_num_probes == E1INP_USE_DEFAULT &&
-			 line->keepalive_probe_interval == E1INP_USE_DEFAULT)
-			vty_out(vty, " e1_line %u keepalive%s", line->num,
-				VTY_NEWLINE);
-		else
+		else if (line->keepalive_idle_timeout != E1INP_USE_DEFAULT ||
+			 line->keepalive_num_probes != E1INP_USE_DEFAULT ||
+			 line->keepalive_probe_interval != E1INP_USE_DEFAULT)
 			vty_out(vty, " e1_line %u keepalive %d %d %d%s",
 				line->num,
 				line->keepalive_idle_timeout,