staging: rtl8188eu: cmdThread is a task_struct

cmdThread is the return value of kthread_run, i.e. a struct task_struct.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20210419201126.25633-3-martin@kaiser.cx


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>