wl12xx: call extended radio parameters for wl127x AP mode

We need to set the extended radio parameters for wl127x only.
Currently, we were only calling this command with wl127x STA mode, but
we should also do it for AP mode.

Move the call to the extended radio paramaters to the common hw_init
and use a single if for the chip type to do everything at once.

Signed-off-by: Luciano Coelho <coelho@ti.com>