mwl8787: drop dead non-mp sdio write code

The multiport code has been working fine for a while.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
mwl8787: don't adjust rate_idx for MCS rates

Signed-off-by: Bob Copeland <me@bobcopeland.com>
mwl8787: trace irqs and log the rd/wr bitmaps

Signed-off-by: Bob Copeland <me@bobcopeland.com>