pgsql: Define META_FREE in a way that doesn't cause -Wempty-body warnin

Define META_FREE in a way that doesn't cause -Wempty-body warnings.

That get rids of the only -Wempty-body warning when compiling postgres
with gcc 4.8/9. As 6550b901f shows, it's useful to be able to use that
option routinely.

Without asserts there's many more warnings, but that's food for
another commit.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/9b6bb9b47153e4bf6d23bef13165491ba440fc23

Modified Files
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contrib/fuzzystrmatch/dmetaphone.c |    2 +-
1 file changed, 1 insertion(+), 1 deletion(-)