adds build targets for auto completion

Makefile

@@ -85,6 +85,8 @@ echo_if_silent = VERBOSE=1
 $(VERBOSE)echo_if_silent = echo $1
 $(VERBOSE)SILENT := @
 
+BUILD_TARGETS := $(BUILD_TARGETS)
+CHECK_TARGETS := $(CHECK_TARGETS)
 CONTAINER_GROUP := $(CONTAINER_GROUP)
 VERSION := $(VERSION)
 PROJECT_ROOT := $(PROJECT_ROOT)
@@ -102,6 +104,10 @@ $(addprefix $(OUT)/docker/,$(ARM_TARGETS)): $(OUT)/docker/qemu-arm-static-$(QEMU
 
 $(addprefix $(OUT)/docker/,$(UBUNTU_TARGETS)): CODENAME := $(UBUNTU_CODENAME)
 
+$(CHECK_TARGETS):
+
+$(BUILD_TARGETS):
+
 .PHONY: all
 all: $(BUILD_TARGETS)
 
@@ -133,8 +139,6 @@ get-deps: $(EXTRACT_TARGETS)
 debug-print-%:
 	@printf '%s\n' '$*:' $($*)
 
-$(BUILD_TARGETS):
-
 $(CHECK_TARGETS): GLOAS := test
 $(CHECK_TARGETS): CONTAINER_USER := user