fix Issue 18117 - ldiv_t struct in core.stdc.stdlib -- int vs c_long …

[huglovefan]

…expectations

classic c_long mismatch

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	18117	minor	ldiv_t struct in core.stdc.stdlib -- int vs c_long expectations

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 + druntime#3789"