Signed-off-by: Devaraj Ranganna <devaraj.ranganna@arm.com>

The blinky example prints `psa_framework_version` by invoking PSA API
from TF-M. In addition, it also prints `LED on` and `LED off` to
simulate LED blinking.

Signed-off-by: Devaraj Ranganna <devaraj.ranganna@arm.com>