UBIFS: fix error path in create_default_filesystem()
UBIFS: fix error path in create_default_filesystem()

In the end of 'create_default_filesystem()' we need to check
the return value of 'ubifs_write_node()' to ensure that we have
successfully written the 'cs_node'.

Signed-off-by: hujianyang <8cccc8a0252a9ef1c303b177e69000167d8d42b6@huawei.com>
Signed-off-by: Artem Bityutskiy <2f96f8cd3e2780a209d0ab27d1b44624d0019d3f@linux.intel.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs