pgsql: Fix typos - Mailing list pgsql-committers

Fix typos

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/d93c05635f4290109ee39d95bf181543428a6977

Modified Files
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config/c-compiler.m4       | 4 ++--
src/include/pg_config.h.in | 5 +++--
2 files changed, 5 insertions(+), 4 deletions(-)