brcmfmac: restrict dongle txglom disable to old SDIO core

txglomming is a firmware feature for sdio bus interface. For SDIO
device cores newer than revision 11, the default setting of
firmware should be used instead of disabling it from the host side.

Reviewed-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Franky Lin <frankyl@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>