brcmfmac: firmware shared data version fix

Firware shared data structure is backward compatible for fields
we are interested in.
Allow reading of shared data in case of version mismatch.

Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Arend van Spriel <arend@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Piotr Haber <phaber@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>