Rename product_services to system_ext

Bug: 134359158
Test: build and check if system_ext.img is created
Change-Id: I67f2e95dd29eac6a28e07e24ea973d3a134c3bfc
diff --git a/core/soong_app_prebuilt.mk b/core/soong_app_prebuilt.mk
index d873cc4..8fc2e4c 100644
--- a/core/soong_app_prebuilt.mk
+++ b/core/soong_app_prebuilt.mk
@@ -43,7 +43,7 @@
   endif # TURBINE_ENABLED != false
 endif
 
-# Run veridex on product, product_services and vendor modules.
+# Run veridex on product, system_ext and vendor modules.
 # We skip it for unbundled app builds where we cannot build veridex.
 module_run_appcompat :=
 ifeq (true,$(non_system_module))