pgsql-server: Use sizeof() rather than strlen() in array size.

Log Message:
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Use sizeof() rather than strlen() in array size.

Modified Files:
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pgsql-server/src/port:
path.c (r1.19 -> r1.20)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/src/port/path.c.diff?r1=1.19&r2=1.20)