brcmfmac: Fix oops when SDIO device is removed.

brcmfmac: Fix oops when SDIO device is removed.

On removal of SDIO card both functions of card will be getting
a remove call. When the first is hanging in ctrl frame xmit then
the second will cause oops. This patch fixes the xmit ctrl
handling in case of serious errors and also limits the handling
for remove to function 1 only.

Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Daniel (Deognyoun) Kim <dekim@broadcom.com>
Signed-off-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>