Release Notes for OpenPower Firmware v1.21.2

This is a point release on top of op-build v1.21.

Like v1.21, this release is NOT intended for GA POWER9 platforms, for that, op-build v2.0 is required.

Changes since v1.21.1:

• skiboot 5.10.2
  • Tie tm-suspend fw-feature and opal_reinit_cpus() together
• kernel: Move to Linux 4.14.24-openpower1