Write clean_steps.mk with multiple commands

$(INTERNAL_CLEAN_STEPS) could be too big to be fit in a single
command line.

Bug: 26707439
Change-Id: Ieed6c772980d06c2418a9246b025bca7a6f568aa
diff --git a/core/cleanbuild.mk b/core/cleanbuild.mk
index 06ceecb..f7722d2 100644
--- a/core/cleanbuild.mk
+++ b/core/cleanbuild.mk
@@ -122,9 +122,17 @@
   mkdir -p $(dir $(clean_steps_file)) && \
   echo "CURRENT_CLEAN_BUILD_VERSION := $(INTERNAL_CLEAN_BUILD_VERSION)" > \
       $(clean_steps_file) ;\
-  echo "CURRENT_CLEAN_STEPS := $(INTERNAL_CLEAN_STEPS)" >> \
-      $(clean_steps_file) \
+  echo "CURRENT_CLEAN_STEPS := $(wordlist 1,500,$(INTERNAL_CLEAN_STEPS))" >> $(clean_steps_file) \
  )
+define -cs-write-clean-steps-if-arg1-not-empty
+$(if $(1),$(shell echo "CURRENT_CLEAN_STEPS += $(1)" >> $(clean_steps_file)))
+endef
+$(call -cs-write-clean-steps-if-arg1-not-empty,$(wordlist 501,1000,$(INTERNAL_CLEAN_STEPS)))
+$(call -cs-write-clean-steps-if-arg1-not-empty,$(wordlist 1001,1500,$(INTERNAL_CLEAN_STEPS)))
+$(call -cs-write-clean-steps-if-arg1-not-empty,$(wordlist 1501,2000,$(INTERNAL_CLEAN_STEPS)))
+$(call -cs-write-clean-steps-if-arg1-not-empty,$(wordlist 2001,2500,$(INTERNAL_CLEAN_STEPS)))
+$(call -cs-write-clean-steps-if-arg1-not-empty,$(wordlist 2501,3000,$(INTERNAL_CLEAN_STEPS)))
+$(call -cs-write-clean-steps-if-arg1-not-empty,$(wordlist 3001,99999,$(INTERNAL_CLEAN_STEPS)))
 endif
 
 CURRENT_CLEAN_BUILD_VERSION :=