pgsql: Fix reading of BitString nodes

Fix reading of BitString nodes

The node tokenizer went out of its way to store BitString node values
without the leading 'b'.  But everything else in the system stores the
leading 'b'.  This would break if a BitString node is
read-printed-read.

Also, the node tokenizer didn't know that BitString node tokens could
also start with 'x'.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/4159834.1657405226@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2cb1a5a8d4aeb63da2d6a2d22169f05c60bb5828

Modified Files
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src/backend/nodes/read.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)