Fix Issue 20643 - printf without arguments aborts compilation

[Luhrel]

We shouldn't return an error, because it is deprecated for the moment.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✗	20643	minor	printf without arguments aborts compilation

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#10921"

[MoonlightSentinel]

Needs a compilable test