plproxy - plproxy: Remove unused CONST token.

Log Message:
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Remove unused CONST token.

Noticed by Hiroshi Saito

Modified Files:
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plproxy/src:
parser.y (r1.11 -> r1.12)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/src/parser.y.diff?r1=1.11&r2=1.12)
scanner.l (r1.8 -> r1.9)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/plproxy/plproxy/src/scanner.l.diff?r1=1.8&r2=1.9)