Merge pull request #7005 from Diederikvanderpant/bugfix-1.1.x

added shift register pins for reprapworld keypad v1.1

Marlin/pins_MEGATRONICS_2.h

 #define BTN_EN2            59
 #define BTN_ENC            43
 
+// Buttons that are attached using shift register of reprapworld keypad  v1.1
+#define SHIFT_CLK 63
+#define SHIFT_LD 42
+#define SHIFT_OUT 17
+#define SHIFT_EN 17
+
 //
 // M3/M4/M5 - Spindle/Laser Control
 //