pgsql: jit: Create void type in the right context

jit: Create void type in the right context

Commit 3b991f81c45 introduced a specific context for types such
that all no longer referenced types can be dropped periodically
rather than leaking. One void pointer type creation was however
missed leading to an assertion failure in LLVM Debug builds.

Per buildfarm members canebreak and urutu.  Fix with assistance
from Andres. The codepath in question was refactored in version
13 hence why this only affected version 12.

Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1106876.1700409912@sss.pgh.pa.us

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c922b241064ceadc95c49fac445e4ed24171b3f0

Modified Files
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src/backend/jit/llvm/llvmjit_expr.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)