brcm80211: fmac: update bus state in common driver part

The bus state is updated in the sdio bus init function, but it is
better to do it when the brcmf_bus_start() function is completed
successfully. The brcmf_netdev_open() function will return -EAGAIN
until the state is updated instead of calling brcmf_bus_start() to
avoid reentering that function.

Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>