pgsql: Fix error reporting after ioctl() call with pg_upgrade --clone

Fix error reporting after ioctl() call with pg_upgrade --clone

errno was not reported correctly after attempting to clone a file,
leading to incorrect error reports. While scanning through the code, I
have not noticed any similar mistakes.

Error introduced in 3a769d8.

Author: Justin Pryzby
Discussion: /messages/by-id/20220731134135.GY15006@telsasoft.com
Backpatch-through: 12

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/523926dea97f360f1f785853eea49e4dc4a6e1e9

Modified Files
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src/bin/pg_upgrade/file.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)