Update readme to inlude steps to set up sms-cv

Description

• Currently the sms-cv is included as submodule in the orchestration repo
• In the Readme of the orchestration repo there are not steps described, how to set up the sms-cv

Todos

• Add description on how to set up the sms-cv in the README
  • The following commands should be included:
    • git submodule init
    • git submodule update