of: Define board compatible for MINIX NEO-X8

Document the board compatible property for MINIX NEO-X8, a
Meson8-based digital media player. While at it, move the other
existing Meson board compatible to amlogic.txt.

Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Signed-off-by: Carlo Caione <carlo@endlessm.com>
2 files changed