[PATCH 0/5] MR5986: Cmd engine rewrite (part XIV)

[eric pouech (＠epo)]

This is part XIV of cmd engine rewrite.

It mainly tests and sets return code for a couple of directory related
commands (CD, MKDIR/MD, PUSHD, DIR).
It's on purpose that POPD isn't included in this MR:
  it will require (as RMDIR) some changes not directly related
  to command itself (more on next MR).