dawn: update to 2021-08-05

dawn: update to 2021-08-05

* c70773a - datastorage: use signal strength as a metric
* 14e0f83 - Don't display debugging output with DAWN_NO_OUTPUT
* 97e5de1 - uci: add neighbor list priority options
* 2b1a53c - dawn_uci: set default values
* 6eb747b - Use separate configs for 802.11g & 802.11a bands
* 1e34357 - Verify compatibility before parsing config message
* a7a8309 - List all neighbors with same score when kicking
* 3ba0fa4 - Change beacon request fields to appropriate values
* 009aab9 - Change mode config parameter from int to string

Signed-off-by: Nick Hainke <vincent@systemli.org>