pgsql: Fix under-parenthesized macro definitions

Fix under-parenthesized macro definitions

Lack of parens in the definitions could cause a statement using these
macros to have unexpected semantics.  In current code no bug is
apparent, but best to fix the definitions to avoid problems down the
line.

Reported-by: Tom Lane
Discussion: https://postgr.es/m/19795.1568400476@sss.pgh.pa.us

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/00f167bed782363b4fe05ecd870155eb84336a8b

Modified Files
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src/include/nodes/parsenodes.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)