pgsql: Remove ipc_test.

Remove ipc_test.

This doesn't seem to be useful any more, and it's not really worth the
effort to keep updating it every time relevant dependencies or calling
signatures in the shared memory or semaphore code change.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/b8a721149b190dc09c00620f65cb85b190b83d45

Modified Files
--------------
src/backend/port/Makefile   |    4 -
src/backend/port/ipc_test.c |  334 -------------------------------------------
2 files changed, 338 deletions(-)