Update doc/developer-guides/hld/hld-devicemodel.rst

Co-Authored-By: dbkinder <david.b.kinder@intel.com>

Author: Geoffroy Van Cutsem

doc/developer-guides/hld/hld-devicemodel.rst

@@ -189,7 +189,7 @@ s, pci_slot <slot_config>
 
    Where:
 
-   - slot is 0..31
+   - ``slot`` is 0..31
    - func is 0..7
    - emul is a string describing the type of PCI device e.g. virtio-net
    - config is an optional device-dependent string, used for