osd: remove deadcode

The variable is_ver1 is always true and so OSD_CAP_LEN can never be
used.

Reported by Coverity.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Acked-by: Boaz harrosh <ooo@elecrozaur.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>