Add dependency for combined aconfig files

Bug: 293436986
Test: manual
Change-Id: I1d358faf9a0a3a83a92646c7cf7194c17ad2331e
diff --git a/core/packaging/flags.mk b/core/packaging/flags.mk
index 4b692be..af52c81 100644
--- a/core/packaging/flags.mk
+++ b/core/packaging/flags.mk
@@ -75,7 +75,7 @@
 define generate-partition-aconfig-flag-file
 $(eval $(strip $(1)): PRIVATE_OUT := $(strip $(1)))
 $(eval $(strip $(1)): PRIVATE_IN := $(strip $(3)))
-$(strip $(1)): $(ACONFIG)
+$(strip $(1)): $(ACONFIG) $(strip $(3))
 	mkdir -p $$(dir $$(PRIVATE_OUT))
 	$$(if $$(PRIVATE_IN), \
 		$$(ACONFIG) dump --format textproto --out $$(PRIVATE_OUT) \