[core] Fixed mem leak in parse worker thread

The problem was that a struct containing the struct work_struct was allocated and passed to the INIT_WORK macro, but the memory location was never freed.

Signed-off-by: Christina Quast <chrysh.ng+github@gmail.com>
[drbcc-wd] Fixed return in wd options

Signed-off-by: Christina Quast <chrysh.ng+github@gmail.com>