lib/syscall-stubs: Trigger regeneration on configheader changes

Before aosp/3527960, vm-x86_64-test_os built arm64 targets. Unfortunately, the
change does not trigger a full rebuild but causes the incremental build to fail.

This change introduces a dependency on generated files to configheader
to detect build configuration changes.

Bug: 399565091
Test: build.py vm-x86_64-test_os-userdebug
Change-Id: Ie3b9890e5c41796005015ed0175bd9d3a926178d

lib/syscall-stubs/rules.mk

diff --git a/lib/syscall-stubs/rules.mk b/lib/syscall-stubs/rules.mk
index 7a8f865..d47fbea 100644
--- a/lib/syscall-stubs/rules.mk
+++ b/lib/syscall-stubs/rules.mk
@@ -30,7 +30,7 @@
 $(SYSCALL_S): SYSCALL_H:=$(SYSCALL_H)
 $(SYSCALL_S): SYSCALL_S:=$(SYSCALL_S)
 $(SYSCALL_S): SYSCALL_RS:=$(SYSCALL_RS)
-$(SYSCALL_S): $(SYSCALL_TABLE) $(SYSCALL_STUBGEN_TOOL)
+$(SYSCALL_S): $(SYSCALL_TABLE) $(SYSCALL_STUBGEN_TOOL) $(CONFIGHEADER)
 	@$(MKDIR)
 	@echo generating syscalls stubs $@
 	$(NOECHO)$(SYSCALL_STUBGEN_TOOL) --arch $(ARCH) -d $(SYSCALL_H) -s $(SYSCALL_S) -r $(SYSCALL_RS) $<