Replace IS_ERR_OR_NULL test with an IS_ERR test since
ion_device_create() function returns a valid device or a -PTR_ERR
only as evidenced by the comment on the function prototype.
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>