✨ DGUS_LCD_UI followup (#25175)

Co-authored-by: Scott Lahteine <thinkyhead@users.noreply.github.com>

Author: ellensp

Marlin/src/inc/SanityCheck.h

@@ -4325,6 +4325,8 @@ static_assert(_PLUS_TEST(4), "HOMING_FEEDRATE_MM_M values must be positive.");
     #error "DGUS_LCD_UI IA_CREALITY requires CLASSIC_JERK."
   #elif DISABLED(BABYSTEPPING)
     #error "DGUS_LCD_UI IA_CREALITY requires BABYSTEPPING."
+  #elif NUM_RUNOUT_SENSORS > 1
+    #error "DGUS_LCD_UI IA_CREALITY requires NUM_RUNOUT_SENSORS < 2."
   #elif NONE(AUTO_BED_LEVELING_BILINEAR, AUTO_BED_LEVELING_UBL, MESH_BED_LEVELING)
     #error "DGUS_LCD_UI IA_CREALITY requires AUTO_BED_LEVELING_BILINEAR, AUTO_BED_LEVELING_UBL, or MESH_BED_LEVELING."
   #endif