Log Message:
fix reboot on pinebook-pro.

pull in \ 
https://github.com/ARM-software/arm-tru … 516b8785ec
from upstream, and also force this code path to be used.

bump version of both the rk3399 ATF and the pbp u-boot, and adjust
the buildlink version to require the updated ATF.

fix MESSAGE for u-boot-pinebook-pro to not refer to rockpro64.