pgsql: Remove dead code in toast_fetch_datum_slice

Remove dead code in toast_fetch_datum_slice

In toast_fetch_datum_slice(), we Assert() that what is passed in isn't
compressed, but we then later had a check to see what the length of if
what was passed in is compressed. That later check is rather confusing
since toast_fetch_datum_slice() is only ever called with non-compressed
datums and the Assert() earlier makes it clear that one shouldn't be
passing in compressed datums.

Add a comment to make it clear that toast_fetch_datum_slice() is just
for non-compressed datums, and remove the dead code.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/96c702c1edbde8a3f5013bd0ac6c25c85710258d

Modified Files
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src/backend/access/heap/tuptoaster.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)