wifi: Create apex mainline module

Bug: 144722612
Test: Device boots up and connects to wifi networks.
Change-Id: I35d7f349b7baaa389fbaf7368eeca22e20274e96
diff --git a/Android.bp b/Android.bp
index 7c74fcb..5c41f75 100644
--- a/Android.bp
+++ b/Android.bp
@@ -16,5 +16,7 @@
     "libwifi_system",
     "libwifi_system_iface",
     "service",
+    "service/apex",
+    "service/proto",
     "tests",
 ]