zephyr: nrf52840_pca10056: use flash defines from DTS
#define FLASH_DRIVER_NAME CONFIG_SOC_FLASH_NRF5_DEV_NAME
#define FLASH_ALIGN 4
-#define FLASH_AREA_IMAGE_0_OFFSET 0x08000
-#define FLASH_AREA_IMAGE_0_SIZE 0x6C000
-#define FLASH_AREA_IMAGE_1_OFFSET 0x74000
-#define FLASH_AREA_IMAGE_1_SIZE 0x6C000
-#define FLASH_AREA_IMAGE_SCRATCH_OFFSET 0xE0000
-#define FLASH_AREA_IMAGE_SCRATCH_SIZE 0x1D000
/* Flash sector size is provided by SoC include */
