wifi: Isolate wifi configurations for customization.

add gs101/wifi/BoardConfig-wifi.mk.

Bug: 208159314
Test: ifconfig after attempting STA+SAP concurrency.
Change-Id: I5f1d52c36da220361aff2840596c9fb95fc40719
diff --git a/raven/BoardConfig.mk b/raven/BoardConfig.mk
index 4ff656e..2b67f76 100644
--- a/raven/BoardConfig.mk
+++ b/raven/BoardConfig.mk
@@ -23,6 +23,7 @@
   USES_DEVICE_GOOGLE_RAVIOLE := true
 
   include device/google/gs101/BoardConfig-common.mk
+  include device/google/gs101/wifi/BoardConfig-wifi.mk
   -include vendor/google_devices/gs101/prebuilts/BoardConfigVendor.mk
   -include vendor/google_devices/raven/proprietary/BoardConfigVendor.mk
 endif