Add additional HBA information to sr-probe or sr-create without a scsiID.

There currently is no easy way to gather basic information about HBAs, which
are required for the provisioning of external storage.
The only way to access this information is to manually collect it via Dom0.

This commit adds very basic information about the availiable FC and iSCSI HBAs
to the HBA-specific output of "xe-srobe type=LVMoHBA" and "xe-create
type=LVMoHBA" to address this gap.

Signed-off-by: Robert Breker <robert.breker@citrix.com>