pgsql: pg_waldump: Improve option parsing error messages

pg_waldump: Improve option parsing error messages

I rephrased the error messages to be more in the style of
option_parse_int(), and also made use of the new "detail" message
facility. I didn't actually use option_parse_int() (which could be
used for -n) because libpgfeutils wasn't used here yet and I wanted to
keep this just to string changes. But it could be done in the future.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/25f915b31e41e5c86e1905d199c7d41cc66161ed

Modified Files
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src/bin/pg_waldump/pg_waldump.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)