[pushed] Fix sim build failure

[Tom Tromey <tom@tromey.com>]

On x86-64 Fedora 32, the sim was failing to build.
sim_events_schedule was passing a 'dummy' argument to
sim_events_schedule_vtracef, which caused an error because the format
parameter was NULL.  However, removing this dummy argument caused an
error because too few arguments were being passed -- catch 22.

This patch fixes the build problem by using sim_events_schedule_tracef
instead.

sim/common/ChangeLog
2021-04-22  Tom Tromey  <tom@tromey.com>

	* sim-events.c (sim_events_schedule): Use
	sim_events_schedule_tracef.
---
 sim/common/ChangeLog    | 5 +++++
 sim/common/sim-events.c | 5 +----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/sim/common/sim-events.c b/sim/common/sim-events.c
index 207c8674d16..60e4c55a874 100644
--- a/sim/common/sim-events.c
+++ b/sim/common/sim-events.c
@@ -469,10 +469,7 @@ sim_events_schedule (SIM_DESC sd,
 		     sim_event_handler *handler,
 		     void *data)
 {
-  va_list dummy;
-  memset (&dummy, 0, sizeof dummy);
-  return sim_events_schedule_vtracef (sd, delta_time, handler, data,
-				      NULL, dummy);
+  return sim_events_schedule_tracef (sd, delta_time, handler, data, NULL);
 }
 #endif
 
-- 
2.26.2