Revert "Add extracting OROCOS_TARGET from the environment"
Revert "Add extracting OROCOS_TARGET from the environment"

This reverts commit d49b3544a86e9f172dce7a1a10251931484ea422.

The CMake code should *not* get OROCOS_TARGET from the environment, but from the
CMake variable definitions

doudou/modelkit-component,doudou/modelkit-component