brcmfmac: Correctly handle accesses to SDIO func0

Rather than workaround the restrictions on func0 addressing in the
driver, set MMC_QUIRK_LENIENT_FN0

Signed-off-by: Ian Molton <ian@mnementh.co.uk>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>