With 24 MHz accesses to the SD card were unreliable. And the chance of
failure recently got worse, so that logging became impossible.

 * working debugging (one click build and debug)
   * SITL jmavsim
   * SITL gazebo
   * jlink px4_fmu-v{2-5}
 * improved syntax highlighting
   * GNU linker files
   * ROS message files msg/*.msg
   * jinja2 template files
 * fixed intellisense support

 - starts requirements for PX4 modules (hrt, param, etc)

- fixes #11009

Not all boards have an SD card.

This is a *breaking* change and requires a bootloader change.

 - explicitly set TOOLCHAIN on all NuttX targets