pgsql: Remove remnants of ImmediateInterruptOK handling.

Remove remnants of ImmediateInterruptOK handling.

Now that nothing sets ImmediateInterruptOK to true anymore, we can
remove all the supporting code.

Reviewed-By: Heikki Linnakangas

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/2505ce0be0b686c5a0a5141e9d080e7fdc35988a

Modified Files
--------------
src/backend/storage/ipc/ipc.c         |    2 --
src/backend/tcop/postgres.c           |   29 -------------------------
src/backend/utils/error/elog.c        |   29 +++----------------------
src/backend/utils/init/globals.c      |    1 -
src/backend/utils/misc/timeout.c      |   38 +++------------------------------
src/include/miscadmin.h               |    1 -
src/test/modules/test_shm_mq/worker.c |    6 +-----
7 files changed, 7 insertions(+), 99 deletions(-)