[secureboot] only remove exec bit in secureboot

[Staphylo]

Address issue #4832

[qiluo-msft]

Thanks!

[lguohan]

@qiluo-msft, can you link the issue in the pr?

[daall]

retest vsimage please

[jleveque]

Retest vsimage please

[qiluo-msft]

@jleveque Please do not retest when there is one already running. Sometimes there are multiple triggered, and each finished one will mark failure here. I aborted the latest one. Thanks for your helping!

[jleveque]

@qiluo-msft: The vsimage check build was showing as failed, which is why I issued the retest. If it was still running, it wasn't reflected properly here.

[lguohan]

Retest vsimage please

[ciju-juniper]

This fixes #4646
Built an image and tested.

[qiluo-msft]

Sorry @Staphylo, I don't know what happens to Github. After I merge this PR, the commit shows my name 719c8e6

Credit should go to you.

[jleveque]

Interesting. GitHub used to display "<user x> authored and <user y> committed". Maybe something changed with the new redesign?

[Staphylo]

No worries, I don't mind it. The fix was the important thing ^^

[qiluo-msft]

It turns out somehow I mistakenly merge instead of squash merge, so there is fork and merge in the history and your original commit is also in the history before.