Issue #401: Report `hw.network.bandwidth.limit` in bytes/s

Implemented the megaBit2Byte conversion in the Mapping processor.
Reported hw.network.io{direction="transmit|receive"} in bytes per second instead of bytes per millisecond.
Corrected the computation of hw.network.bandwidth.utilization to ensure that both the dividend and divisor are in the same unit (bytes).
Adjusted the power estimator for network devices because hw.network.bandwidth.limit is now measured in bytes.

sentrysoftware / metricshub