pgsql: Tolerate EINVAL when calling fsync() on a directory.

Tolerate EINVAL when calling fsync() on a directory.

Previously, we tolerated EBADF as a way for the operating system to
indicate that it doesn't support fsync() on a directory.  Tolerate
EINVAL too, for older versions of Linux CIFS.

Bug #15636.  Back-patch all the way.

Reported-by: John Klann
Discussion: https://postgr.es/m/15636-d380890dafd78fc6@postgresql.org

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/bcf6278343444aa1de93b7c131b30c608a5b6e45

Modified Files
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src/backend/storage/file/fd.c | 2 +-
src/common/file_utils.c       | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)