MKS SGEN L V2 adaptable heaters/fans (#19462)

Marlin/src/pins/lpc1769/pins_MKS_SGEN_L_V2.h

@@ -207,20 +207,20 @@
 //
 #define HEATER_BED_PIN                     P2_05
 #define HEATER_0_PIN                       P2_07
-#if HOTENDS == 1
+#if HAS_MULTI_HOTEND
-  #ifndef FAN1_PIN
-    #define FAN1_PIN                       P2_06
-  #endif
-#else
   #ifndef HEATER_1_PIN
     #define HEATER_1_PIN                   P2_06
   #endif
+#else
+  #ifndef FAN2_PIN
+    #define FAN2_PIN                       P2_06  // HE1 for FAN3
+  #endif
 #endif
 #ifndef FAN_PIN
-  #define FAN_PIN                          P2_04
+  #define FAN_PIN                          P2_04  // FAN1
 #endif
-#ifndef FAN2_PIN
+#ifndef FAN1_PIN
-  #define FAN2_PIN                         P1_04
+  #define FAN1_PIN                         P1_04  // FAN2
 #endif
 
 //