Add progress indicator to Android.mk includes

Test: m -j
Change-Id: I1e6fd020a06b49c243be14953d9f417e64ac7b8b
diff --git a/core/definitions.mk b/core/definitions.mk
index 137bddf..a7f720d 100644
--- a/core/definitions.mk
+++ b/core/definitions.mk
@@ -3241,6 +3241,11 @@
 #$(warning 42 == $(call math_max,5,42))
 #$(warning 42 == $(call math_max,42,5))
 
+# $1 is the variable name to increment
+define inc_and_print
+$(strip $(eval $(1) := $($(1)) .)$(words $($(1))))
+endef
+
 ###########################################################
 ## Other includes
 ###########################################################
diff --git a/core/main.mk b/core/main.mk
index dff0163..492ea8b 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -547,8 +547,10 @@
 #
 
 subdir_makefiles := $(SOONG_ANDROID_MK) $(call first-makefiles-under,$(TOP))
+subdir_makefiles_total := $(words $(subdir_makefiles))
+.KATI_READONLY := subdir_makefiles_total
 
-$(foreach mk,$(subdir_makefiles),$(info including $(mk) ...)$(eval include $(mk)))
+$(foreach mk,$(subdir_makefiles),$(info [$(call inc_and_print,subdir_makefiles_inc)/$(subdir_makefiles_total)] including $(mk) ...)$(eval include $(mk)))
 
 ifdef PDK_FUSION_PLATFORM_ZIP
 # Bring in the PDK platform.zip modules.