Add received optical power monitoring from Samtec FF to the data sent to grafana

[pwittich]

Add received optical power to the monitoring of the 4 channel transceivers and the 12 channel receivers.

Based on the data sheets, neither the 14 G 12 channel receiver nor the CERN-B receiver have this information available.

The 25 G 12 channel receiver appears to have the 12 channel registers on Upper page 0x1. The data is a 16 bit unsigned integer calibrated to 0.1 uW/LSB. "The low byte within each pair is the MSB." The data is laid out starting at address 206/207 through 228/229 for channel 11 to channel 0, respectively. Register is called RSSI. No further information in v3 of the data sheet (page 65).

The 25 G 4 channel transceivers appear to have this on page 0x0, with the same data format. The addresses are starting at 34/35 for Ch 1 and end at 40/41 for channel 4 (opposite order from the 12 channel part, and here 1-based numbering.) This is based on v1 of the data sheet, on page 52.

[dgastler]

Please also add the LOS LOL OS and clk sel signals (some are i2c registers in your layout) for the Si chips to the monitoring so it can easily be checked on the SM.