Add system/logging/liblog.

This is needed so it can run bindgen tests.

Test: Build
Change-Id: Iefcd1077e3b572c662474c4bb461b04dc66c6204
diff --git a/rust/config/allowed_list.go b/rust/config/allowed_list.go
index 926d2ac..ee9be6e 100644
--- a/rust/config/allowed_list.go
+++ b/rust/config/allowed_list.go
@@ -25,6 +25,7 @@
 		"system/extras/simpleperf",
 		"system/hardware/interfaces/keystore2",
 		"system/librustutils",
+		"system/logging/liblog",
 		"system/logging/rust",
 		"system/security",
 		"system/tools/aidl",