LibreELEC for Khadas VIM1 VIM2 VIM3 (SD & USB & eMMC)

Added Libreelec images 20180425 for S912 (VIM2).

Duplicates information from this thread. This may help users understand what happens when they install LE on the eMMC in the future.

If the media has “dtb.img”, then first install in the eMMC there is replaced by the dtb, the new version (the new "dtb.img " is written instead of the previous one in eMMC). Description of the layout of the partitions in the eMMC in the new dtb, may not coincide with the description in the dtb, which was in eMMC. Therefore, if you encounter startup problems after installing into the eMMC, you must perform a re-installation (without changing the “dtb.img”), what would reinstalling the recorded data in the correct sections.