apex: Remove host support

Since we no longer support "zip" APEX, we don't need "host" support.

For example, we don't need go/python binary support.

Bug: 279835185
Test: m
Change-Id: I6e8d2b205e42662f31866dc9ac7507524effd144
diff --git a/apex/key.go b/apex/key.go
index 3010d76..65e739a 100644
--- a/apex/key.go
+++ b/apex/key.go
@@ -60,7 +60,7 @@
 func ApexKeyFactory() android.Module {
 	module := &apexKey{}
 	module.AddProperties(&module.properties)
-	android.InitAndroidArchModule(module, android.HostAndDeviceDefault, android.MultilibCommon)
+	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibCommon)
 	android.InitBazelModule(module)
 	return module
 }