lib/trusty: tipc-test should not print results to error stream

tipc-test results cannot be parsed in the CI because they output to
error stream

Bug: 314130383
Test: /data/nativetest64/vendor/tipc-test/tipc-test -t echo -r 1 -B 100
Change-Id: I2d6506fd69af06338041035526ca759884719c7b
diff --git a/trusty/libtrusty/tipc-test/tipc_test.c b/trusty/libtrusty/tipc-test/tipc_test.c
index 1eac9cf..3cf0c05 100644
--- a/trusty/libtrusty/tipc-test/tipc_test.c
+++ b/trusty/libtrusty/tipc-test/tipc_test.c
@@ -1041,7 +1041,7 @@
     }
     avg /= params->bench;
 
-    fprintf(stderr, BENCH_RESULT_TPL, params->test_name, min, max, avg, cold, min, max, avg, cold);
+    printf(BENCH_RESULT_TPL, params->test_name, min, max, avg, cold, min, max, avg, cold);
     return rc;
 }