协议栈
版本：nRF5_SDK_15.3.0_59ac345
#define SD_FLASH_SIZE 0x26000
app：
0x26000-0x77000
bootloader
0x77000-0x7e000
MBR params
0x7e000-7f000
bootloader setting:
7f000-80000
ref:
https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sr3nrf52.firmware/memory_configuration.html