ssl-opt.sh: include test name in log files

This is a convenience for when we get log files from failed CI runs, or attach
them to bug reports, etc.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 717689f..8046eb7 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -509,19 +509,19 @@
 
         # run the commands
         if [ -n "$PXY_CMD" ]; then
-            echo "$PXY_CMD" > $PXY_OUT
+            printf "# $NAME\n$PXY_CMD\n" > $PXY_OUT
             $PXY_CMD >> $PXY_OUT 2>&1 &
             PXY_PID=$!
             wait_proxy_start "$PXY_PORT" "$PXY_PID"
         fi
 
         check_osrv_dtls
-        echo "$SRV_CMD" > $SRV_OUT
+        printf "# $NAME\n$SRV_CMD\n" > $SRV_OUT
         provide_input | $SRV_CMD >> $SRV_OUT 2>&1 &
         SRV_PID=$!
         wait_server_start "$SRV_PORT" "$SRV_PID"
 
-        echo "$CLI_CMD" > $CLI_OUT
+        printf "# $NAME\n$CLI_CMD\n" > $CLI_OUT
         eval "$CLI_CMD" >> $CLI_OUT 2>&1 &
         wait_client_done