Don't call __delay_4cycles for 0 cycle delay - takes a really long time. (#11586)

Marlin/src/HAL/shared/Delay.h

       }
       #undef MAXNOPS
     }
-    else
-      __delay_4cycles(x / 4);
+    else if ((x >>= 2))
+      __delay_4cycles(x);
   }
   #undef nop
 
 
       #undef MAXNOPS
     }
-    else
-      __delay_4cycles(x / 4);
+    else if ((x >>= 2))
+      __delay_4cycles(x);
   }
   #undef nop