pgsql: Move resowner from common JitContext to LLVM specific

Move resowner from common JitContext to LLVM specific

Only the LLVM specific code uses it since resource owners were made
extensible in commit b8bff07daa85c837a2747b4d35cd5a27e73fb7b2. This is
new in v17, so backpatch there to keep the branches from diverging
just yet.

Author: Andreas Karlsson <andreas@proxel.se>
Discussion: https://www.postgresql.org/message-id/fd3a2a00-6605-4e30-a118-48418b478e6e@proxel.se

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5784a493f14e02ece767aec7b4d3ed96e16a3a20

Modified Files
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src/backend/jit/llvm/llvmjit.c | 10 +++++-----
src/include/jit/jit.h          |  2 --
src/include/jit/llvmjit.h      |  3 +++
3 files changed, 8 insertions(+), 7 deletions(-)