move all nrf boards into its family group

hw/bsp/nrf/family.mk

@@ -1,3 +1,5 @@
+include $(TOP)/$(BOARD_PATH)/board.mk
+
 CFLAGS += \
   -flto \
   -mthumb \
@@ -6,7 +8,6 @@ CFLAGS += \
   -mfloat-abi=hard \
   -mfpu=fpv4-sp-d16 \
   -DCFG_TUSB_MCU=OPT_MCU_NRF5X \
-  -DNRF52840_XXAA \
   -DCONFIG_GPIO_AS_PINRESET
 
 # suppress warning caused by vendor mcu driver
@@ -26,7 +27,7 @@ LDFLAGS += -L$(TOP)/hw/mcu/nordic/nrfx/mdk
 SRC_C += \
   hw/mcu/nordic/nrfx/drivers/src/nrfx_power.c \
   hw/mcu/nordic/nrfx/drivers/src/nrfx_uarte.c \
-  hw/mcu/nordic/nrfx/mdk/system_nrf52840.c
+  hw/mcu/nordic/nrfx/mdk/system_$(MCU_VARIANT).c
 
 INC += \
   $(TOP)/$(BOARD_PATH) \
@@ -38,7 +39,7 @@ INC += \
   $(TOP)/hw/mcu/nordic/nrfx/drivers/include \
   $(TOP)/hw/mcu/nordic/nrfx/drivers/src \
 
-SRC_S += hw/mcu/nordic/nrfx/mdk/gcc_startup_nrf52840.S
+SRC_S += hw/mcu/nordic/nrfx/mdk/gcc_startup_$(MCU_VARIANT).S
 
 ASFLAGS += -D__HEAP_SIZE=0
 
@@ -50,7 +51,7 @@ CHIP_FAMILY = nrf5x
 FREERTOS_PORT = ARM_CM4F
 
 # For flash-jlink target
-JLINK_DEVICE = nRF52840_xxAA
+JLINK_DEVICE = $(MCU_VARIANT)_xxaa
 
 # For uf2 conversion
 UF2_FAMILY = 0xADA52840