wl18xx: align wl18xx_conf_phy with FW variant and remove it

wl18xx_conf_phy represents part of the FW native wl18xx_mac_and_phy_params
structure. Remove it and replace the phy part of the wl18xx conf with the
FW bound structure. This allows us to set/override all members.

Increment the wlconf version to ensure compatibility with the new
structure

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>