Description of CPU in Web Interface in Device>Inventory is blank

Some implementations of snmp do not fill the field hrDeviceDescr for processor-resources. After the fix of #1009 these CPUs remain in the inventory of devices but are shown in the web interface on page "Device>Inventory" with a blank description field.

I did't figure out if the workaround-description should be saved in the db nor why it's not written to db in case it should be there.

But I created a quick workaround for this - see attached svn-diff