Add check if exec_op is set before calling it.
At the moment it is called unconditionally, which leads to a crash if it
is not set correctly.
Signed-off-by: NBernhard Messerklinger <bernhard.messerklinger@br-automation.com>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>
Reviewed-by: NJagan Teki <jagan@amarulasolutions.com>