wl12xx: 1281/1283 support - New radio structs and functions

New general and radio parameters structures and functions.
Implemented as separate functions due to auto-detection
between wl127x and wl128x.

Signed-off-by: Shahar Levi <shahar_levi@ti.com>
Reviewed-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>