pgsql: Remove latch.c workaround for Linux < 2.6.27.

Remove latch.c workaround for Linux < 2.6.27.

Commit 82ebbeb0 added a workaround for systems with no epoll_create1()
and EPOLL_CLOEXEC. Linux < 2.6.27 and glibc < 2.9 are long gone. Now
seems like a good time to drop the extra code, because otherwise we'd
have to add similar already-dead workaround code to new patches using
XXX_CLOEXEC flags that arrived in the same kernel release.

Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/CA%2BhUKGKL_%3DaO%3Dr30N%3Ds9VoDgTqHpRSzePRbA9dkYO7snc7HsxA%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d1b90995e8d41df7e59efe48e98f26cd66baba9b

Modified Files
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src/backend/storage/ipc/latch.c | 21 +--------------------
1 file changed, 1 insertion(+), 20 deletions(-)