pgsql: Quick adaption of JIT tuple deforming to the fast default patch.

Quick adaption of JIT tuple deforming to the fast default patch.

Instead using memset to set tts_isnull, call the new
slot_getmissingattrs().

Also fix a bug (= instead of >=) in the code generation. Normally = is
correct, but when repeatedly deforming fields not in a
tuple (e.g. deform up to natts + 1 and then natts + 2) >= is needed.

Discussion: https://postgr.es/m/20180328010053.i2qvsuuusst4lgmc@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f4f5845b3182ab930e525b1419bca47ac611604e

Modified Files
--------------
src/backend/access/common/heaptuple.c | 8 +++-
src/backend/jit/llvm/llvmjit.c | 2 +
src/backend/jit/llvm/llvmjit_deform.c | 85 +++++++++++++----------------------
src/backend/jit/llvm/llvmjit_types.c | 1 +
src/include/executor/tuptable.h | 1 +
src/include/jit/llvmjit.h | 1 +
6 files changed, 41 insertions(+), 57 deletions(-)