scsi: vmw-pvscsi: return DID_BUS_BUSY for adapter-initated aborts

The vmw_pvscsi driver returns DID_ABORT for commands aborted internally
by the adapter, leading to the filesystem going read-only. Change the
result to DID_BUS_BUSY, causing the kernel to retry the command.

Signed-off-by: Jim Gill <jgill@vmware.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>