Should be another / separate SCSI adapter used for the disk where the SQL Server is running with all the databases?
The drivers in a VM are ALL the same, there is no difference from a performance perspective. they do offer different features and capability however, and SOME tools report a performance difference because of caching and different ways the controller interacts with the host.
You will not get any benefit from adding another controller in a VM, the only thing that WILL happen is you get more overhead managing another SCSI controller. The hypervisor puts traffic across ONE controller, so adding multiple controllers in a VM just means they will ALL be routed to the same physical controller on the host.
So SQL in a VM does NOT need Logs/data/temp separated, THOSE specs (read the SQL documents CAREFULLY) are specifically for LOCAL drives, that's what people keep missing. SAN doesn't matter, separating data across different LUNs doesn't matter, if it does.. you didn't setup the SAN correctly, because the SAN does this for you. LOCAL disks however, because the controllers are using 4 or 6 spindles usually, NEED to separate the traffic for OS/Logs/Temp/DATA on SEPARATE drives, that's why SQL recommends that, but those techniques do NOT apply to the SAN or VM, because VM's are not able to separate drive traffic, that's controlled by the hypervisor, and the VM can't access the drives directly.
So keep it simple, one controller, one big drive for SQL, don't SHARE SQL VM with other applications (keep in mind I am talking about the VM itself NOT data on the SAN). So don't install other apps in a SQL instance VM!
If you do that, performance will be fine.