Let BlDisplayInputDialog() work on a copy of input text and save it only on ENTER key press

xtldr2/includes/bootman.h

@@ -60,6 +60,12 @@ VOID
 BlDisplayInfoDialog(IN PWCHAR Caption,
                     IN PWCHAR Message);
 
+XTCDECL
+VOID
+BlDisplayInputDialog(IN PWCHAR Caption,
+                     IN PWCHAR Message,
+                     IN OUT PWCHAR *InputFieldText);
+
 XTCDECL
 XTBL_DIALOG_HANDLE
 BlDisplayProgressDialog(IN PWCHAR Caption,