pgsql: fsync test files Prevent creation of 16GB files during fsync

Log Message:
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fsync test files

Prevent creation of 16GB files during fsync testing; only create 16MB
files; backpatch to 8.4.X.

Tags:
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REL8_4_STABLE

Modified Files:
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pgsql/src/tools/fsync:
test_fsync.c (r1.23.2.1 -> r1.23.2.2)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/tools/fsync/test_fsync.c?r1=1.23.2.1&r2=1.23.2.2)