brcmsmac: rework switch control table init including iPA BT-combo

Rework the code path in lcnphy tbl_init() for switch control
table programming. This also takes the iPA BT-combo card into
account.

Tested-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>