isl: update to 0.23 (with cloog and soname)

[dkwo]

General

• This is a new package and it conforms to the quality requirements

Have the results of the proposed changes been tested?

• I use the packages affected by the proposed changes on a regular basis and confirm this PR works for me
• I generally don't use the affected packages but briefly tested this PR

[dkwo]

See also #24424
This time I only revbump cloog.

[dkwo]

@pullmoll @tornaria how does it look now?

[ericonr]

You're updating two packages here, you should have a commit for each.

[dkwo]

@ericonr Thanks, I think I fixed it.

[tornaria]

Looks good to me, I compiled sagemath-9.2 using this without any issue.

[ericonr]

The isl commit message should mention that it's fixing the license and homepage.

[dkwo]

@ericonr is the cloog repo fine or should I revert it back to the previous (obsolete) one?

[ericonr]

Ok, I think the cloog commit should mention that it's changing the distfiles origin, but otherwise LGTM. Just fix the commit message and we are good.

[dkwo]

@ericonr Done.