Lib_deps #include paths are messed up

Interesting how mbed-os builds libraries then. The mbed_lib.json doesn’t explicitly declare any include directories. Seems to automagically include all paths in a library then?

Anyways, bug report in GitHub - platformio/builder-framework-mbed: ARM mbed build script for PlatformIO Build System please because I think that just including the library folder as -I path is not what mbed-os does.

CC @valeros