pgsql: Improve recording of IA64 stack data.

Improve recording of IA64 stack data.

Examination of the results from anole and gharial suggests that we're
only managing to track the size of one of the two stacks of IA64 machines.
Some googling gave the answer: on HPUX11, the register stack is reported
as a page type I don't see in pstat.h on my HPUX10 box.  Let's try
testing for that.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c57562725d219c4249b82f4a4fb5aaeee3ae0d53

Modified Files
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src/backend/storage/ipc/ipc.c | 26 ++++++++++++++++++++------
1 file changed, 20 insertions(+), 6 deletions(-)