pgsql: pg_basebackup: Fix a couple of recently-introduced bugs.

pg_basebackup: Fix a couple of recently-introduced bugs.

The server expects the compression level to be between 1 and 9, but
Z_DEFAULT_COMPRESSION is -1, so we must not try to send that value
to the server.

Because pg_basebackup's -R option is implemented on the client side,
it can't be used in combination with a backup target. Error out if
someone tries that, instead of silently ignoring the option.

Both issues were reported by Tushar Ahuja; patch by me.

Discussion: http://postgr.es/m/CA+TgmoaMwgdx8HxBjF8hmbohVvPL_0H5LqNrSq0uU+7BKp_Q2A@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dabf63bc9a5b71f61c2c8712c85d33fdc06efa8c

Modified Files
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src/bin/pg_basebackup/pg_basebackup.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)