wifi: brcmfmac: initialize SDIO data work before cleanup

Summary

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: initialize SDIO data work before cleanup brcmf_sdio_probe() stores the newly allocated bus in sdiodev->bus before allocating the ordered workqueue. If that allocation fails, the function jumps to fail and calls brcmf_sdio_remove(). brcmf_sdio_remove() unconditionally cancels bus->datawork. Initialize the work item before the first failure path that can reach brcmf_sdio_remove(), so the cleanup path always observes a valid work object. This issue was found by our static analysis tool and then confirmed by manual review of the probe error path and the remove-time work drain. The problem pattern is an early setup failure that reaches a cleanup helper which cancels an embedded work item before its initializer has run. A QEMU PoC forced alloc_ordered_workqueue() to fail at the same point in brcmf_sdio_probe(), before INIT_WORK(&bus->datawork) is reached. The resulting fail path calls brcmf_sdio_remove(), and DEBUG_OBJECTS reports the invalid work drain with brcmf_sdio_probe() and brcmf_sdio_remove() in the stack.