split keyboard input logic into platform specific code

src/tabcontrollers/keyboardinput/KeyboardInputDummy.cpp

@@ -0,0 +1,20 @@
+#include "KeyboardInputDummy.h"
+
+namespace advsettings {
+
+void KeyboardInputDummy::sendKeyboardInput(QString input)
+{
+    // noop
+}
+
+void KeyboardInputDummy::sendKeyboardEnter()
+{
+    // noop
+}
+
+void KeyboardInputDummy::sendKeyboardBackspace(int count)
+{
+    // noop
+}
+
+}