images: add build-images-min target

Only builds base image, none of the others.

Makefile

@@ -77,6 +77,7 @@ help:
 	@echo "  all: builds all the tools directly in this repo"
 	@echo "  clean: cleans all the tool folders in this repo"
 	@echo "  build-images: prepare prereqs for VMs (images directory)"
+	@echo "  build-images-min: prepare minimal prereqs for VMs"
 	@echo "  documentation: build documentation in doc/build_"
 	@echo "  external: clone and build our tools in external repos "
 	@echo "            (qemu, gem5, ns-3)"

images/rules.mk

@@ -35,6 +35,9 @@ TAS_IMAGE := $(d)output-tas/tas
 IMAGES := $(UBUNTU_IMAGE) $(BASE_IMAGE) $(NOPAXOS_IMAGE) $(MEMCACHED_IMAGE)
 RAW_IMAGES := $(addsuffix .raw,$(IMAGES))
 
+IMAGES_MIN := $(UBUNTU_IMAGE) $(BASE_IMAGE)
+RAW_IMAGES_MIN := $(addsuffix .raw,$(IMAGES_MIN))
+
 img_dir := $(d)
 packer := $(d)packer
 
@@ -52,6 +55,9 @@ guest_init := $(d)/scripts/guestinit.sh
 
 build-images: $(IMAGES) $(RAW_IMAGES) $(vmlinux) $(bz_image) $(mqnic_mod)
 
+build-images-min: $(IMAGES_MIN) $(RAW_IMAGES_MIN) $(vmlinux) $(bz_image) \
+    $(mqnic_mod)
+
 ################################################
 # Disk image