Merge changes from topic "allwinner-idle" into integration

* changes:
  feat(allwinner): provide CPU idle states to the rich OS
  feat(allwinner): simplify CPU_SUSPEND power state encoding
  feat(allwinner): choose PSCI states to avoid translation
  feat(fdt): add the ability to supply idle state information
  fix(allwinner): improve DTB patching error handling
  refactor(allwinner): patch the DTB after setting up PSCI
  refactor(allwinner): move DTB change code into allwinner/common