Intel boot agent question

[Phil]

Thank you for reading this.

This question relates to a Lenevo ThinkPad T420.

About 18 months ago I used Clonezilla to clone a small SSD to a larger 
one. I only did this because I need to keep Windows 7 to update my 
Garmin navigator from time to time, otherwise I would have just 
installed Kubuntu on the whole drive.

This worked well, except I cannot reboot Linux or Windows. Attempted 
reboots cause Intel's boot agent to start and after a brief time  a boot 
selection list is displayed; the list does not contain the SSD.

During the past 18 months I've searched the Internet for a solution but 
haven't found anything that looks like a solid answer. It seems to me 
that, somehow, the boot drive needs to be added to the selection list.

Any suggestions will be gratefully appreciated. Powering off and then 
restarting is getting to be a real pain.

-- 
Regards,
Phil