staging: lustre: lnet: fix improper return value

At the end of function lstcon_group_info(), "return 0" seems improper.
It may be better to return the value of rc.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=188811Signed-off-by: NPan Bian <bianpan2016@163.com>
Acked-by: NOleg Drokin <oleg.drokin@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lnet/selftest/console.c

@@ -823,7 +823,7 @@ lstcon_group_info(char *name, lstcon_ndlist_ent_t __user *gents_p,
 
 	lstcon_group_decref(grp);
 
-	return 0;
+	return rc;
 }
 
 static int