core: wire up flash make target for Teensy 4.x (#13077)

related to https://github.com/kinx-project/kint/issues/5

platforms/chibios/IC_TEENSY_4_1/board/board.mk

@@ -0,0 +1 @@
+include $(CHIBIOS_CONTRIB)/os/hal/boards/PJRC_TEENSY_4_1/board.mk

platforms/chibios/IC_TEENSY_4_1/rules.mk

@@ -0,0 +1 @@
+TEENSY_LOADER_CLI_MCU = imxrt1062

tmk_core/chibios.mk

@@ -390,8 +390,10 @@ ifndef TEENSY_LOADER_CLI
     endif
 endif
 
+TEENSY_LOADER_CLI_MCU ?= $(MCU_LDSCRIPT)
+
 define EXEC_TEENSY
-	$(TEENSY_LOADER_CLI) -mmcu=$(MCU_LDSCRIPT) -w -v $(BUILD_DIR)/$(TARGET).hex
+	$(TEENSY_LOADER_CLI) -mmcu=$(TEENSY_LOADER_CLI_MCU) -w -v $(BUILD_DIR)/$(TARGET).hex
 endef
 
 teensy: $(BUILD_DIR)/$(TARGET).hex cpfirmware sizeafter
@@ -408,6 +410,8 @@ else ifeq ($(strip $(BOOTLOADER)),kiibohd)
 	$(call EXEC_DFU_UTIL)
 else ifeq ($(strip $(MCU_FAMILY)),KINETIS)
 	$(call EXEC_TEENSY)
+else ifeq ($(strip $(MCU_FAMILY)),MIMXRT1062)
+	$(call EXEC_TEENSY)
 else ifeq ($(strip $(MCU_FAMILY)),STM32)
 	$(call EXEC_DFU_UTIL)
 else