Merge INITRAMFS_DIR and ROOTFS_DIR variables

Author: gsingh93

Makefile

@@ -86,8 +86,7 @@ help:
 	@echo ''
 	@echo '   Environment Variables:'
 	@echo '      EXT4_SIZE                     - The disk size of the rootfs image to build'
-	@echo '      INITRAMFS_DIR                 - The directory to create the initramfs from (default: rootfs/alpine-$$ARCH)'
-	@echo '      ROOTFS_DIR                    - The directory to create the ext4/rootfs image from (default: rootfs/alpine-$$ARCH)'
+	@echo '      ROOTFS_DIR                    - The directory to create the ext4 rootfs image and initramfs CPIO from (default: rootfs/alpine-$$ARCH)'
 	@echo '      ROOTFS                        - The path to the rootfs image file (default: rootfs/rootfs-$$ARCH.img)'
 	@echo '      ROOTFS_FORMAT                 - The format of the rootfs image file (default: qcow2)'
 	@echo ''
@@ -242,8 +241,7 @@ ROOTFS_PARENT_DIR := $(ROOT_DIR)/rootfs
 ROOTFS ?= $(ROOTFS_PARENT_DIR)/rootfs-$(ARCH).img
 ROOTFS_FORMAT ?= qcow2
 ROOTFS_DIR ?= $(ROOTFS_PARENT_DIR)/alpine-$(ARCH)
-INITRAMFS_DIR ?= $(ROOTFS_DIR)
-CPIO_FILE ?= $(ROOTFS_PARENT_DIR)/$$(basename $(INITRAMFS_DIR)).cpio.gz
+CPIO_FILE ?= $(ROOTFS_PARENT_DIR)/$$(basename $(ROOTFS_DIR)).cpio.gz
 EXT4_SIZE ?= 1G
 
 # The user might set a relative path for `CPIO_FILE`, so we need to get the
@@ -272,15 +270,14 @@ ext4: | $(ROOTFS_DIR)
 	mv $(ROOTFS).tmp $(ROOTFS)
 
 .PHONY: cpio initramfs
-initramfs cpio: | $(INITRAMFS_DIR)
-	(cd $(INITRAMFS_DIR) && find . -print0 \
+initramfs cpio: | $(ROOTFS_DIR)
+	(cd $(ROOTFS_DIR) && find . -print0 \
 		| cpio --null --create --verbose --format=newc) \
 		| gzip --best > $(CPIO_FILE)
 
 .PHONY: uncpio
-uncpio:
-	mkdir -p $(INITRAMFS_DIR)
-	cd $(INITRAMFS_DIR) && zcat $(CPIO_FILE) | cpio --extract --make-directories --format=newc --no-absolute-filenames
+uncpio: | $(ROOTFS_DIR)
+	cd $(ROOTFS_DIR) && zcat $(CPIO_FILE) | cpio --extract --make-directories --format=newc --no-absolute-filenames
 
 .PHONY: rootfs
 rootfs: ext4 cpio