🩹 SKR2 Pins DIAG flag (#23968)

Followup to #23050

Marlin/src/pins/stm32f4/pins_BTT_SKR_V2_0_common.h

@@ -23,6 +23,8 @@
 
 #include "env_validate.h"
 
+#define USES_DIAG_JUMPERS
+
 // If you have the BigTreeTech driver expansion module, enable BTT_MOTOR_EXPANSION
 // https://github.com/bigtreetech/BTT-Expansion-module/tree/master/BTT%20EXP-MOT
 //#define BTT_MOTOR_EXPANSION