The Pine boots, Weston shows on a HDMI display. [skip ci]: doesn't finish in time; ollieparanoid tested that this compiles for armhf, aarch64, armv7
* Added linux-postmarketos-allwinner kernel * Added copy of alpines u-boot package with pine-a64lts support * Changed postmarketos-mkinitfs to add the plain .dtb file to the boot partition