clean up lpc55 boards

hw/bsp/lpc55/boards/lpcxpresso55s28/board.mk

@@ -1,8 +1,8 @@
 MCU_VARIANT = LPC55S28
 MCU_CORE = LPC55S28
+PORT ?= 1
 
 CFLAGS += -DCPU_LPC55S28JBD100
-PORT ?= 1
 
 JLINK_DEVICE = LPC55S28
 PYOCD_TARGET = LPC55S28

hw/bsp/lpc55/boards/lpcxpresso55s69/board.mk

@@ -1,8 +1,8 @@
 MCU_VARIANT = LPC55S69
 MCU_CORE = LPC55S69_cm33_core0
+PORT ?= 1
 
 CFLAGS += -DCPU_LPC55S69JBD100_cm33_core0
-PORT ?= 1
 
 JLINK_DEVICE = LPC55S69
 PYOCD_TARGET = LPC55S69

hw/bsp/lpc55/boards/mcu_link/board.mk

@@ -1,8 +1,6 @@
-PORT ?= 1
-SPEED ?= high
-
 MCU_VARIANT = LPC55S69
 MCU_CORE = LPC55S69_cm33_core0
+PORT ?= 1
 
 CFLAGS += -DCPU_LPC55S69JBD64_cm33_core0