VMware: enable VMware driver to use new BDM format

This patch makes the necessary changes in the driver to enable
it to use some of the features of the new block device mapping format.

After this patch it will be possible to set the bus, and device_type per
block device.

Change-Id: Idcf3dd97c3baacd77d03616b5b2dd768acf46de4
Merge "VMware: enable VMware driver to use new BDM format"