brcmfmac: Rename / replace old IO functions with simpler ones.

Primarily this patch removes:

brcmf_sdiod_f0_writeb()
brcmf_sdiod_reg_write()
brcmf_sdiod_reg_read()

Since we no longer use the quirky method of deciding which function to
address via the address being accessed, take the opportunity to rename
some IO functions more in line with common kernel code. We also convert
those that map directly to sdio_{read,write}*() to macros.

Signed-off-by: Ian Molton <ian@mnementh.co.uk>
Reviewed-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>