Add dark variant for OpenWrt

[Smankusors]

Proposed change

The images are from the https://github.com/openwrt/branding

I decided to use the white and blue as a dark variant so that it's consistent with the rest of HA blue logos, wdyt?

before	after

I also updated the light logo variant according to that repo so that it's consistent with the new dark variant

I wonder since there are identical images from core_brands and custom_integrations, shall I create a symlink? Like the existing core integrations of ubus and luci?
Or should I left these core_brands and custom_integrations as is?
nvm, I read the README, the custom_integrations should not symlink to the core_brands

Thanks,

Type of change

• Add a new logo or icon for a new core integration
• Add a missing icon or logo for an existing core integration
• Add a new logo or icon for a custom integration (custom component)
  • I've added a link to my custom integration repository in the PR description
  • I've opened up a PR for my custom integration on the Home Assistant
    Python wheels repository
• Replace an existing icon or logo with a higher quality version
• Replace an existing icon or logo after a branding change
• Removing an icon or logo

Additional information

• This PR fixes or closes issue: fixes #
• Link to code base pull request:
• Link to documentation pull request:
• Link to integration documentation on our website: https://www.home-assistant.io/integrations/luci/ https://www.home-assistant.io/integrations/ubus/
• Link to custom integration repository: https://github.com/kvj/hass_openwrt https://github.com/dscao/openwrt

Checklist

• The added/replaced image(s) are PNG
• Icon image size is 256x256px (icon.png)
• hDPI icon image size is 512x512px for (icon@2x.png)
• Logo image size has min 128px, but max 256px, on the shortest side (logo.png)
• hDPI logo image size has min 256px, but max 512px, on the shortest side (logo@2x.png)

[frenck]

Thanks, @Smankusors 👍

../Frenck