pgsql: Fix pg_basebackup with in-place tablespaces.

Fix pg_basebackup with in-place tablespaces.

Previously, pg_basebackup from a cluster that contained an 'in-place'
tablespace, as introduced by commit 7170f215, would produce a harmless
warning on Unix and fail completely on Windows.

Reported-by: Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com>
Reviewed-by: Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com>
Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Discussion: https://postgr.es/m/20220304.165449.1200020258723305904.horikyota.ntt%40gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c6f2f01611d4f2c412e92eb7893f76fa590818e8

Modified Files
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src/backend/access/transam/xlog.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)