Update/cbmc submodule may 2020

[martin-cs]

No description provided.

[martin-cs]

This updates to the last working CBMC version. diffblue/cbmc#5210 breaks some of the gnat2goto regression tests. If @xbauch has a moment, an opinion on how to fix it would be most appreciated.

[chrisr-diffblue]

@martin-cs Petr left Diffblue at the end of Feb I think, so I'm not sure if he is likely to have time/interest in working on CBMC/gnat2goto anymore.

[tjj2017]

I can certainly see that the cvmc submodule has been updated.
I haven't tried to review all of the individual changes in cbmc.

[tjj2017]

The cbmc submodule has certainly been updated.
I have not reviewed the individual cbmc changes.

[martin-cs]

@chrisr-diffblue : thanks. I was going to @ the reviewers of the diffblue/cbmc#5210 but then I noticed I reviewed that so I really should be able to figure it out.
Would it be possible to add @tjj2017 as an approved reviewer?

@xbauch : apologies.

[chrisr-diffblue]

@martin-cs I'll look into getting Trevor added as an approved reviewer. I'm not 100% sure I have full authority to do so, but I'll check.

[chrisr-diffblue]

@martin-cs @tjj2017 I don't have appropriate permissions to add Trevor as a collaborator, but Peter Schrammel should have just sent Trevor an invite - as soon as Trevor accepts the invite he should be an approved reviewer.

[martin-cs]

Thanks for the prompt and positive response.