pgsql: Add missing outfuncs.c support for struct InhRelation.

Add missing outfuncs.c support for struct InhRelation.

This is needed to support debug_print_parse, per report from Jon Nelson.
Cursory testing via the regression tests suggests we aren't missing
anything else.

Branch
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REL8_2_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=ef35f36b794923cbe7d2afa0d21e3fade994bfcd

Modified Files
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src/backend/nodes/outfuncs.c |   12 ++++++++++++
1 files changed, 12 insertions(+), 0 deletions(-)