cmake: support other emulation platforms/runners

Right now we are hardcoded to only qemu, with the native port, we make
this more generic and support this in a plugin mode where a running has
its own cmake definitons implementing the various targets.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Signed-off-by: Alberto Escolar Piedras <alpi@oticon.com>
3 files changed