wifi: brcmfmac: Fix potential kernel oops when probe fails

In the Linux kernel, the following vulnerability has been resolved:

wifi: brcmfmac: Fix potential kernel oops when probe fails

When probe of the sdio brcmfmac device fails for some reasons (i.e.

missing firmware), the sdiodev->bus is set to error instead of NULL, thus

the cleanup later in brcmf_sdio_remove() tries to free resources via

invalid bus pointer. This happens because sdiodev->bus is set 2 times:

first in brcmf_sdio_probe() and second time in brcmf_sdiod_probe(). Fix

this by chaning the brcmf_sdio_probe() function to return the error code

and set sdio->bus only there.