pgsql: postgres_fdw: Remove redundant check in semijoin_target_ok()

postgres_fdw: Remove redundant check in semijoin_target_ok()

If a var belongs to the innerrel of the joinrel, it's not possible that
it belongs to the outerrel. This commit removes the redundant check from
the if-clause but keeps it as an assertion.

Discussion: https://postgr.es/m/flat/CAHewXN=8aW4hd_W71F7Ua4+_w0=bppuvvTEBFBF6G0NuSXLwUw(at)mail(dot)gmail(dot)com
Author: Tender Wang <tndrwang(at)gmail(dot)com>
Reviewed-by: Alexander Pyhalov <a(dot)yhalov(at)postgrespro(dot)ru>
Backpatch-through: 17

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/62f36d6924c740b5a566d64c563789d20cd4a5e1

Modified Files
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contrib/postgres_fdw/postgres_fdw.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)