Log Message:-----------Add "SSD" acronym mention for solid state drive mention.
Modified Files:-------------- pgsql/doc/src/sgml: wal.sgml (r1.65 -> r1.66) (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/wal.sgml?r1=1.65&r2=1.66)
