pgsql: Avoid shadowing a variable in sync.c.

Avoid shadowing a variable in sync.c.

It was confusing to reuse the variable name 'entry' in two scopes.
Use distinct variable names.

Reported-by: Ranier Vilela <ranier.vf@gmail.com>
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/CAEudQArDrFyQ15Am3rgWBunGBVZFDb90onTS8SRiFAWHeiLiFA%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/57944910585750b52173a0f67c9e0e42639f1c0a

Modified Files
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src/backend/storage/sync/sync.c | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)