Fixed ST7920_DELAY typo

Fixed typo where ST7920_DELAY_2 was being #defined after a check for #ifndef ST7920_DELAY_3

Marlin/pins_SANGUINOLOLU_11.h

@@ -240,7 +240,7 @@
     #ifndef ST7920_DELAY_1
       #define ST7920_DELAY_1 DELAY_0_NOP
     #endif
-    #ifndef ST7920_DELAY_3
+    #ifndef ST7920_DELAY_2
       #define ST7920_DELAY_2 DELAY_3_NOP
     #endif
     #ifndef ST7920_DELAY_3