pgsql: Make memset() use sizeof() rather than re-compute size

Make memset() use sizeof() rather than re-compute size

This is simpler and more closely follows overwhelming precedent.

Report and patch by Mark Dilger.
Discussion: https://postgr.es/m/9A68FB88-5F45-4848-9926-8586E2D777D1@gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3848d21673e9dcb42d4bc1353043d7c7d6f550cd

Modified Files
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src/backend/statistics/extended_stats.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)