pgsql: Minor cleanup of jsonb_util.c

Minor cleanup of jsonb_util.c

Move the functions around to group related functions together. Remove
binequal argument from lengthCompareJsonbStringValue, moving that
responsibility to lengthCompareJsonbPair. Fix typo in comment.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/ff7bbb0176a667aeb0577e4d48d651ffdb6afd50

Modified Files
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src/backend/utils/adt/jsonb_util.c |  378 ++++++++++++++++++------------------
1 file changed, 187 insertions(+), 191 deletions(-)