pgsql: Second thoughts on TOAST decompression.

Second thoughts on TOAST decompression.

On detecting a corrupted match tag, pglz_decompress() should just
summarily return -1. Breaking out of the loop, as I did in dfc797730,
doesn't quite guarantee that will happen. Also, we can use
unlikely() on that check, just in case it helps.

Backpatch to v13, like the previous patch.

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/7957e75c588c0b17210d4379afb50ea2673b0d20

Modified Files
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src/common/pg_lzcompress.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)