Add an example which tests the integration of kleidiai

- Added demonstration of klediai integration as external dependency 

Signed-off-by: Mohammed Suhail Munshi <MohammedSuhail.Munshi@arm.com>

Reviewed-by: Mohammed Suhail Munshi <mohammedsuhail.munshi@arm.com>
Reviewed-by: Emil Ohlsson <emil.ohlsson@arm.com>
Approved-by: Emil Ohlsson <emil.ohlsson@arm.com>