Adds three new sub-commands to nvmeadm:

nvmeadm load-firmware - loads firmware files into the drive's holding area.
nvmeadm commit-firmware - takes the firmware in the holding area and commits to a slot.
nvmeadm activate-firmware - activates a given slot. The firmware in the active slot is loaded by the drive when it is next reset, and becomes the running firmware.

https://www.illumos.org/issues/11203 has an example of how the commands are used.
This process is used by WDC to update NVMe firmware in their IntelliFlash products during manufacturing process.