[LTP] close: add test for double close EBADF

[linuxtestproject.agent@gmail.com]

Hi Jinseok,

our agent completed the review of the patch.

The agent can sometimes produce false positives although often its
findings are genuine. If you find issues with the review, please
comment this email or ignore the suggestions.

On Tue, 14 Apr 2026, Jinseok Kim wrote:
> close: add test for double close EBADF

Reviewed-by: LTP AI Reviewer <ltp-ai@noreply.github.com>

Regards,
LTP AI Reviewer