MegaRAID plugin: Add support of lsm.Disk.rpm and .link_type.
MegaRAID plugin: Add support of lsm.Disk.rpm and .link_type.

 * Since storcli does not expose disk rpm yet, we could only tell HDD
   from SSD.

Signed-off-by: Gris Ge <e24f3acbe39bf94f92e8af3c48f8852106ad5ad7@redhat.com>

cathay4t/libstoragemgmt,tasleson/libstoragemgmt,joehandzik/libstoragemgmt,tasleson/libstoragemgmt,tasleson/libstoragemgmt,libstorage/libstoragemgmt,joehandzik/libstoragemgmt,tasleson/libstoragemgmt,jumitche/libstoragemgmt,cathay4t/libstoragemgmt,libstorage/libstoragemgmt,cathay4t/libstoragemgmt,jumitche/libstoragemgmt,cathay4t/libstoragemgmt,jumitche/libstoragemgmt,jumitche/libstoragemgmt,libstorage/libstoragemgmt,libstorage/libstoragemgmt,tasleson/libstoragemgmt,joehandzik/libstoragemgmt,cathay4t/libstoragemgmt,jumitche/libstoragemgmt,libstorage/libstoragemgmt,joehandzik/libstoragemgmt