wlcore/wl12xx: move wl12xx chip ID defines to the lower driver

Move wl12xx-specific chip ID macros to the wl12xx driver and rename
them to 127X and 128X for clarity since both the "1" (2.4GHz) and the
"3" (2.4GHz and 5GHz) variants use the same chip ID.

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