Clean up makefiles with a source grabber function

user/Makefile

@@ -7,7 +7,7 @@ APP_DIR := $(shell find . -mindepth 1 -maxdepth 1 -type d -not -path "./arch")
 all:
 	rm -f FILES.txt
 	touch FILES.txt
-	for dir in $(APP_DIR); do make -C $$dir FILES=$(CURRENT_DIR)/FILES.txt all; done
+	for dir in $(APP_DIR); do make -C $$dir ROOT=$(ROOT) FILES=$(CURRENT_DIR)/FILES.txt all; done
 
 clean:
 	for dir in $(APP_DIR); do make -C $$dir clean; done

user/hello/Makefile

@@ -1,12 +1,13 @@
+include $(ROOT)/mk/grabsrc.mk
 include ../Makefile.inc
 
 .PHONY: all clean
 
 TARGET := hello
 
-SRCFILES := $(wildcard *.s)
-ASFILES := $(filter %.s,$(SRCFILES))
-OBJ := $(patsubst %.s,%.o,$(ASFILES))
+SRCFILES := $(call GRABSRC, .)
+ASFILES := $(call GET_ASFILES, $(SRCFILES))
+OBJ := $(call GET_OBJ, $(SRCFILES))
 
 %.o: %.s
 	$(CC) $(CFLAGS) -c $< -o $@