I have built a custum kernel from this source code:https://github.com/LineageOS/android_kernel_htc_msm8960
I've the used Linaro 4.9 build tool chain.
I used this tool to repack the boot image: https://github.com/xiaolu/mkbootimg_tools
I've the used Linaro 4.9 build tool chain.
I used this tool to repack the boot image: https://github.com/xiaolu/mkbootimg_tools