Обсуждение: pgsql: Fix a few typos in comments in GiN.

Log Message:
-----------
Fix a few typos in comments in GiN.

Modified Files:
--------------
    pgsql/src/backend/access/gin:
        ginbtree.c (r1.7 -> r1.8)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginbtree.c.diff?r1=1.7&r2=1.8)
        ginbulk.c (r1.8 -> r1.9)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginbulk.c.diff?r1=1.8&r2=1.9)
        ginget.c (r1.6 -> r1.7)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginget.c.diff?r1=1.6&r2=1.7)
        gininsert.c (r1.7 -> r1.8)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/gininsert.c.diff?r1=1.7&r2=1.8)
        ginvacuum.c (r1.11 -> r1.12)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/gin/ginvacuum.c.diff?r1=1.11&r2=1.12)