Add HP ProDesk 400 G4 Small Form Factor PC device-type (#3817)

* Create ProDesk-400-G4-SFF.yaml

* Change module bay positions to string format as per schema

device-types/HP/ProDesk-400-G4-SFF.yaml

@@ -0,0 +1,22 @@
+---
+manufacturer: HP
+model: ProDesk 400 G4 SFF
+slug: hpe-prodesk-400-g4-sff
+part_number: 3SW63UC
+u_height: 6.5
+is_full_depth: false
+weight: 4.6
+weight_unit: kg
+comments: '[HP ProDesk 400 G4 Small Form Factor PC (3SW63UC) - All Tech Specs](https://support.hp.com/ca-en/product/product-specs/hp-prodesk-400-g4-small-form-factor-pc/model/15292381?sku=3sw63uc)'
+power-ports:
+  - name: PSU
+    type: iec-60320-c14
+    maximum_draw: 180
+interfaces:
+  - name: ETH-1
+    type: 1000base-t
+module-bays:
+  - name: pcie-0
+    position: '0'
+  - name: pcie-1
+    position: '1'