acrn: allow to specify the build output folder
Usages: make O=<any folder>
@@ -4,8 +4,8 @@ T := $(CURDIR)
PLATFORM ?= uefi
RELEASE ?= 0
-BUILD_DIR := build
-ROOT_OUT := $(T)/$(BUILD_DIR)
+O ?= build
+ROOT_OUT := $(shell mkdir -p $(O);cd $(O);pwd)
HV_OUT := $(ROOT_OUT)/hypervisor
DM_OUT := $(ROOT_OUT)/devicemodel
TOOLS_OUT := $(ROOT_OUT)/tools
