pgsql: Remove unneeded includes of

Remove unneeded includes of <sys/stat.h>

Since bfb9dfd, none of the files updated in this commit have any stat()
calls, so these inclusions are not necessary, for the same reasons as
233cf6e.

Per discussion with John Naylor.

Discussion: https://postgr.es/m/CAFBsxsGGGX7KD6RxbNoSJzuSc8Gz3hOxcfhTOMLB_hJcm68dKQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2a71de8915b41cb1a927fc7870efb138bbcd0b77

Modified Files
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src/backend/access/heap/rewriteheap.c | 1 -
src/backend/storage/file/copydir.c    | 1 -
src/timezone/pgtz.c                   | 1 -
3 files changed, 3 deletions(-)