[disk] Fix `tag_by_label` when used together with `use_mount` (#10418)
[disk] Fix `tag_by_label` when used together with `use_mount` (#10418)

If tag_by_label and use_mount were both set, we would end up accessing
the devices_label array by mountpoint instead of the actual device path.
DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core,DataDog/integrations-core