Support for Softdevice S140 7.0.1

[n-snyder]

The nRF52840 equipped boards ship with the Nordic's SoftDevice v6.1.1. This legacy version of the Soft Device does not provide long range capability. Version 7.0.1 or later of the Soft Device enables the long range BT 5 functionality of the chip (S=8 coded BLE). As IoT becomes more common, it seems that there would be a number of use cases and high demand for this.

[ukanuk]

The current latest is 7.3.0, checking out release notes from Nordic's Softdevice S140 page shows a number of other improvements since 6.1.1 as well:

• Various bugfixes which sound to me like they improve
  • Pairing / connectivity, e.g. "Fixed an issue where the last advertising event ... may end ... without listening for a CONNECT_IND, SCAN_REQ, AUX_CONNECT_REQ, or AUX_SCAN_REQ packet"
  • Power-on, e.g. "Fixed an issue where wakeup from sleep can take longer, even if the vector table is in RAM"
• Update from Bluetooth 5.0 to 5.2
• Published max call stack usage. Not given in release notes for 6.1.1, given as 1.8 kB in 7.3.0.

Not improvements:

• Very slight increase in RAM and Flash usage
  • Flash from 152.0 kB to 156.0 kB
  • RAM from 5.54 kB to 5.6 kB