logging/vty: do not print deprecated logging commands to stdout

Yes, we don't really need to poison stdout, as some osmo-* binaries
(like osmo-gapk) may want to use it for non-logging purposes.
This printf() call looks like a debugging leftover.

Change-Id: Ida35865b1c0bb3d3567918f8e89c6551c6b34103
diff --git a/src/vty/logging_vty.c b/src/vty/logging_vty.c
index 88ee330..9615943 100644
--- a/src/vty/logging_vty.c
+++ b/src/vty/logging_vty.c
@@ -1007,7 +1007,6 @@
 	OSMO_ASSERT(cmd);
 	cmd->string = talloc_asprintf(cmd, "logging level %s (debug|info|notice|error|fatal)",
 				    name);
-	printf("%s\n", cmd->string);
 	cmd->func = log_deprecated_func;
 	cmd->doc = LEVEL_STR
 		   "Deprecated Category\n";