staging: unisys: visorhba: delete processing of vdiskmgmt commands

We never issue SCSI commands of type CMD_VDISKMGMT_TYPE, so there is no
need to have code that processes their completions.

Signed-off-by: Tim Sell <Timothy.Sell@unisys.com>
Signed-off-by: David Kershner <david.kershner@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>