add pictures to LANCOM 1783vaw over ISDN (#2750)

* add ProDesk 400 G6 MT

* add pictures to LANCOM 1783vaw over ISDN

* try to fix yaml format

* Delete device-types/HP/ProDesk-400-G6-MT.yaml

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

Author: Jon1Games

device-types/LANCOM/1783VAW-over-ISDN.yaml

@@ -7,6 +7,8 @@ u_height: 0
 is_full_depth: false
 weight: 600
 weight_unit: g
+front_image: true
+rear_image: true
 subdevice_role: child
 comments: '[LANCOM 1783VAW Data sheet](https://www.lancom-systems.de/download/LC-1783VAW/DS_1783VAW_DE.pdf)'
 power-ports: