Move {libbacktrace,libunwindstack} from system/core -> system/unwinding/

BUG: 170465278
Test: TH
Change-Id: I7f0d7b1254e7a28a55599aa4ee6bb6f2ac789b60
diff --git a/tools/warn/android_project_list.py b/tools/warn/android_project_list.py
index 88bc52c..82c0fbd 100644
--- a/tools/warn/android_project_list.py
+++ b/tools/warn/android_project_list.py
@@ -118,7 +118,7 @@
     create_pattern('system/core/healthd'),
     create_pattern('system/core/include'),
     create_pattern('system/core/init'),
-    create_pattern('system/core/libbacktrace'),
+    create_pattern('system/unwinding/libbacktrace'),
     create_pattern('system/logging/liblog'),
     create_pattern('system/core/libpixelflinger'),
     create_pattern('system/core/libprocessgroup'),