pgsql: Use size_t instead of Size in pg_waldump

Use size_t instead of Size in pg_waldump

In commit b15c1513984 I missed the memo about not using Size in new
code.

Per complaint from Thomas Munro

Discussion: /messages/by-id/CA+hUKGJkeTVuq5u5WKJm6xkwmW577UuQ7fA=PyBCSR3h9g2GtQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3f8913f683ba99e7135d374541f52c626fcc6eec

Modified Files
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src/bin/pg_waldump/archive_waldump.c | 14 ++++++--------
src/bin/pg_waldump/pg_waldump.h | 4 ++--
2 files changed, 8 insertions(+), 10 deletions(-)