Update includes to to be relative to src directory

Don't use relative imports like `../foo.h` as those depend on the
relative position of both files. Rather than that use imports relative
to the `src` directory, which explicitly is part of the include
directories.

src/displayapp/Colors.h

@@ -1,7 +1,7 @@
 #pragma once
 
 #include <lvgl/src/lv_misc/lv_color.h>
-#include <components/settings/Settings.h>
+#include "components/settings/Settings.h"
 
 namespace Pinetime {
   namespace Applications {