Add description of the new Hybrid RT (hybrid_rt) scenario to the "What is ACRN"
documentation.
Tracked-On: #5203
Signed-off-by: Geoffroy Van Cutsem <geoffroy.vancutsem@intel.com>
Refresh and update the "What is ACRN" document to reflect the latest changes.
Most notably, the scenario definitions have changed.
Signed-off-by: Geoffroy Van Cutsem <geoffroy.vancutsem@intel.com>