[ Upstream commit e229897d373a87ee09ec5cc4ecd4bb2f895fc16b ]
The debugfs_create_dir() function returns error pointers.
It never returns NULL. So use IS_ERR() to check it.
Fixes: e26a5843f7f5 ("NTB: Split ntb_hw_intel and ntb_transport drivers")
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Signed-off-by: Sasha Levin <sashal@kernel.org>
