6494172 fsck core dumps if metadevice name doesn't start with a 'd'

[peter.den...@sun.com]

Author: petede
Repository: /hg/onnv/onnv-gate
Revision: 020e14333a1bd15cc6eb065afa2bb67d9c751bf4
Log message:
6494172 fsck core dumps if metadevice name doesn't start with a 'd'

Files:
        update: usr/src/head/meta.h
        update: usr/src/lib/lvm/libmeta/common/mapfile-vers
        update: usr/src/lib/lvm/libmeta/common/meta_name.c
        update: usr/src/lib/lvm/libpreen/common/mdpreen.c