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/heltec_mesh_pocket/variant.h

@@ -26,7 +26,6 @@ extern "C" {
 #define LED_RED PIN_LED1
 #define LED_BLUE PIN_LED1
 #define LED_GREEN PIN_LED1
-#define LED_CONN LED_BLUE
 #define LED_STATE_ON 0 // State when LED is lit
 
 /*
@@ -99,8 +98,6 @@ No longer populated on PCB
 #define PIN_SPI_MOSI (0 + 5)
 #define PIN_SPI_SCK (0 + 4)
 
-// #define PIN_PWR_EN (0 + 6)
-
 // To debug via the segger JLINK console rather than the CDC-ACM serial device
 // #define USE_SEGGER