Add normalized_total_op_time_ps (on default dvfs) to opstats.device_op_metrics_db, together with the total_op_time_ps, it will give us a weighted average dvfs multiplier, which can be used to calculate dvfs normalized flops utilization and so on.

[copybara-service]

Add normalized_total_op_time_ps (on default dvfs) to opstats.device_op_metrics_db, together with the total_op_time_ps, it will give us a weighted average dvfs multiplier, which can be used to calculate dvfs normalized flops utilization and so on.

• The aggregated dvfs multiplier will be shown in roofline page top as part of the device info, and used for device spec normalization.
• The agg dvfs multiplier will also be used a an identifier if dvfs normalization control knobs should be displayed on UI or not. (show the knob with a valid multiplier, which is >0 and <1)