pgsql: Provide MAP_FAILED if sys/mman.h doesn't.

Provide MAP_FAILED if sys/mman.h doesn't.

On old HPUX this has to be #defined to -1. It might be that other values
are required on other dinosaur systems, but we'll worry about that when
and if we get reports.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c1494b733015bf09d75c362925ec3f2740a77f73

Modified Files
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src/backend/port/sysv_shmem.c | 6 ++++++
1 files changed, 6 insertions(+), 0 deletions(-)