The sdk_12.1.0 nrf52_ble.c implementation was dependent on SDK components.
This has been replaced with the ble_uart.c implementation using a standalone
bluetooth driver implementation without need of SDK components.
Also, sdk.mk has been updated to not use a special linker script.
Script does not really work very well with blocking char read and
async ble notifications printing data when terminal stdout is blocked
by readchar. Bluetooth UART profile implemented in ble_uart.c is
now working with tralamazza's nus_console nodejs script.
Ref: https://github.com/tralamazza/nus_console
Glenn Ruben Bakke