feat: add power_mode/power_name to info output

[AeroNotix]

Adds the power_mode/power_name to the info json output.

Useful for automated monitoring.

[SimonFair]

The same change should be applied to scsiprint.cpp

smartmontools/smartmontools/scsiprint.cpp

Line 3569 in 6af5903

if (powername) {

[robbat2]

@SimonFair nice catch re SCSI power states
I see that nvmeprint.cpp doesn't export ANY information about the current NVME power state; the power table is shown with -x, but not the current state.