Move GET_CONFIGURATION emulation from scsi_send_command() to
scsi_disk_emulate_command().

Also add GET_CONFIGURATION to scsi-defs.h and scsi_command_name().
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>