How to build zenfone kernel

#1 download aosp source code
	cd [working dir]
	repo init -u https://android.googlesource.com/platform/manifest -b android-5.0.0_r7
	repo sync

#2 checkout correct tool-chain
	cd prebuilts/gcc/linux-x86/x86/x86_64-linux-android-4.8
	git checkout tools_r22.2
	cd [working dir]

#3 extract kernel source code to working dir
	tar -zxvf [kernel-source].tar.gz

#4 build 'minigzip' and 'openssl' modules
	source build/envsetup.sh
	lunch aosp_x86-eng
	make minigzip openssl

#5 build kernel image and modules
## define TARGET_DEVICE to overwrite
## available options : 
## 	TARGET_DEVICE=hd  (A500CG/A501CG/A600CG - default)
##	TARGET_DEVICE=fhd (A502CG/A451CG)

	make -f KernelMakefile TARGET_DEVICE=hd build_kernel
  	or
	make -f KernelMakefile TARGET_DEVICE=hd modules_install