[Nbd] [PATCH] nbd: fix ifnullfree.cocci warnings

[kbuild test robot <lkp@...1303...>]

drivers/block/nbd.c:937:2-26: WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values.
drivers/block/nbd.c:918:2-26: WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values.

 NULL check before some freeing functions is not needed.

 Based on checkpatch warning
 "kfree(NULL) is safe this check is probably not required"
 and kfreeaddr.cocci by Julia Lawall.

Generated by: scripts/coccinelle/free/ifnullfree.cocci

CC: Markus Pargmann <mpa@...1897...>
Signed-off-by: Fengguang Wu <fengguang.wu@...1303...>
---

 nbd.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -914,8 +914,7 @@ static int nbd_dev_dbg_init(struct nbd_d
 
 static void nbd_dev_dbg_close(struct nbd_device *nbd)
 {
-	if (nbd->dbg_dir)
-		debugfs_remove_recursive(nbd->dbg_dir);
+	debugfs_remove_recursive(nbd->dbg_dir);
 }
 
 static int nbd_dbg_init(void)
@@ -933,8 +932,7 @@ static int nbd_dbg_init(void)
 
 static void nbd_dbg_close(void)
 {
-	if (nbd_dbg_dir)
-		debugfs_remove_recursive(nbd_dbg_dir);
+	debugfs_remove_recursive(nbd_dbg_dir);
 }
 
 #else  /* IS_ENABLED(CONFIG_DEBUG_FS) */