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/logging/DummyLogger.h

@@ -1,5 +1,5 @@
 #pragma once
-#include "Logger.h"
+#include "logging/Logger.h"
 
 namespace Pinetime {
   namespace Logging {