Add device type for Synology DS2015xs (#3749)

* Add device type for Synology DS2015xs

* Fix indentation for mgmt_only in DS2015xs.yaml

* Update DS2015xs.yaml

* Update model from DS218 to DS2015xs

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Co-authored-by: Harry <Harry@cadby.co.uk>

device-types/Synology/DS2015xs.yaml

@@ -0,0 +1,32 @@
+---
+manufacturer: Synology
+model: DS2015xs
+slug: synology-ds2015xs
+part_number: DS2015xs
+u_height: 0
+weight: 5.3
+weight_unit: kg
+airflow: front-to-rear
+comments: '[Synology DS2015 Specs] (https://global.download.synology.com/download/Document/Hardware/DataSheet/DiskStation/15-year/DS2015xs/enu/Synology_DS2015xs_Data_Sheet_enu.pdf)'
+is_full_depth: false
+interfaces:
+  - name: Lan 1
+    type: 1000base-t
+    mgmt_only: false
+    label: 1GbE RJ45 LAN port 1
+  - name: Lan 2
+    type: 1000base-t
+    mgmt_only: false
+    label: 1GbE RJ45 LAN port 2
+  - name: Lan 3
+    type: 10gbase-x-sfpp
+    mgmt_only: false
+    label: 10Gb SFP+ LAN Port 3
+  - name: Lan 4
+    type: 10gbase-x-sfpp
+    mgmt_only: false
+    label: 10Gb SFP+ LAN Port 3
+power-ports:
+  - name: PSU 1
+    type: iec-60320-c14
+    maximum_draw: 150