pgsql: jit: Reference expression step functions via llvmjit_types.

jit: Reference expression step functions via llvmjit_types.

The main benefit of doing so is that this allows llvm to ensure that
types match - previously that'd only be detected by a crash within the
called function. There were a number of cases where we passed a
superfluous parameter...

To avoid needing to add all the functions to llvmjit.{c,h}, instead
get them from the llvm module for llvmjit_types.c. Also use that for
the functions from llvmjit_types already in llvmjit.h.

Author: Soumyadeep Chakraborty and Andres Freund
Discussion: https://postgr.es/m/CADwEdooww3wZv-sXSfatzFRwMuwa186LyTwkBfwEW6NjtooBPA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b059d2f45685a946da061ee15692fa306bd67f12

Modified Files
--------------
src/backend/jit/llvm/llvmjit.c | 97 +++++++++------------
src/backend/jit/llvm/llvmjit_deform.c | 6 +-
src/backend/jit/llvm/llvmjit_expr.c | 155 ++++++++++++++++------------------
src/backend/jit/llvm/llvmjit_types.c | 44 ++++++++--
src/include/jit/llvmjit.h | 13 +--
5 files changed, 157 insertions(+), 158 deletions(-)