pgsql: In pg_upgrade, clean up handling of invalid directory specificat

In pg_upgrade, clean up handling of invalid directory specification by
checking the stat() errno value more strictly.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1f35944607f1ede7dbb1dc3283d955b96f04ea5e

Modified Files
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contrib/pg_upgrade/exec.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)