Update notes for submitted changes

* Add a configuration for b2120stxh407 ST boards
Update notes for submitted changes

* Use /system/bin/sh instead of mksh
Update notes for submitted changes

* LAVA-1462 - add elapsed time support
Update notes for submitted changes

* Drop use of 'tr' as some Android images omit 'tr'
Update notes for submitted changes

* tr needs to be provided as well as awk - both are busybox applets.
Update notes for submitted changes

* Use /system/bin/sh instead of mksh