ocfs2: Back out change to use OCFS2_MAXQUOTAS in ocfs2_setattr()

ocfs2_setattr() actually needs to really use MAXQUOTAS and not
OCFS2_MAXQUOTAS since it will pass the array over to VFS. Currently
this isn't a problem since MAXQUOTAS == OCFS2_MAXQUOTAS but it would
be once we introduce project quotas.

CC: Mark Fasheh <mfasheh@suse.com>
CC: Joel Becker <jlbec@evilplan.org>
CC: ocfs2-devel@oss.oracle.com
Signed-off-by: Jan Kara <jack@suse.cz>