Remove stale variant.h defines (#9470)

* Remove noop CANNED_MESSAGE_MODULE_ENABLE define

* Remove over-eager warning removal

* Remove unused LED_CONN

* Dead defines removal

* Rename oddball LED pin name

* Rename second oddball LED pin name

* Remove another dead define

variants/nrf52840/ELECROW-ThinkNode-M1/variant.h

@@ -55,7 +55,6 @@ extern "C" {
 #define LED_RED PIN_LED3
 #define LED_BLUE PIN_LED1
 #define LED_GREEN PIN_LED2
-#define LED_CONN PIN_GREEN
 #define LED_STATE_ON 0 // State when LED is lit  // LED灯亮时的状态
 #define PIN_BUZZER (0 + 6)
 /*
@@ -170,8 +169,6 @@ External serial flash WP25R1635FZUIL0
 #define PIN_SPI_MOSI (0 + 22)
 #define PIN_SPI_SCK (0 + 19)
 
-#define PIN_PWR_EN (0 + 6)
-
 // To debug via the segger JLINK console rather than the CDC-ACM serial device
 // #define USE_SEGGER