neutrino: explicitly include vfd/lcd header

Instead of including it everywhere through global.h, just include
the lcd/vfd header where needed. Add a tiny helper header "display.h"
to divert between vfd.h (coolstream) and lcdd.h (everything else).

src/gui/settings_manager.cpp

@@ -40,6 +40,7 @@
 #include <gui/widget/stringinput.h>
 
 #include <driver/screen_max.h>
+#include <driver/display.h>
 #include <system/helpers.h>
 
 #include <sys/vfs.h>