nrf52: add support for GPIO interrupts
nrf52: add macros to decode GPIO PIN and GPIO PORT
nrf52: various cosmetic changes
nrf52: fix GPIO P1 memory address
boards/nrf52840-dk: add support for SPI
boards/nrf52840-dk: add support for LSM6DSL sensor
boards/nrf52840-dk: add support for SX127X radio
* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
nrf52 updates
board/arm/nrf52/nrf52832-dk: use the on-board virtual COM pins as default UART0 configuration
board/arm/nrf52: initial support for the nrf52840-dk board
board/arm/nrf52: initial support for the nrf52840-dk dongle board
arch/arm/src/nrf52: add support for port 1 GPIO
arch/arm/src/nrf52: initial support for UART1
arch/arm/src/nrf52: add UICR definitions
Approved-by: Gregory Nutt <gnutt@nuttx.org>
