pgsql: Be less detailed about reporting shared memory failure by avoidi

Be less detailed about reporting shared memory failure by avoiding the
output of actual Postgres parameter _values_ related to shared memory,
and suggesting that these are only possible parameters to reduce.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/67a5e727c8655496013b007d2fb6137fcc244b18

Modified Files
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src/backend/port/sysv_shmem.c |   17 ++++++++---------
1 files changed, 8 insertions(+), 9 deletions(-)