timing.c: use memset to initialize the structure, from Gilles Peskine

Signed-off-by: Gianfranco Costamagna <locutusofborg@debian.org>
Signed-off-by: Gianfranco Costamagna <costamagnagianfranco@yahoo.it>
diff --git a/library/timing.c b/library/timing.c
index 8bc1b42..2777f6f 100644
--- a/library/timing.c
+++ b/library/timing.c
@@ -399,8 +399,9 @@
     int hardfail = 0;
     struct mbedtls_timing_hr_time hires;
     uint32_t a = 0, b = 0;
-    mbedtls_timing_delay_context ctx = {};
+    mbedtls_timing_delay_context ctx;
 
+    memset(ctx, 0, sizeof(ctx));
     if (verbose != 0) {
         mbedtls_printf("  TIMING tests note: will take some time!\n");
     }