[cmake] Fix ninja (fixes: #15008)

[wsnipex]

Description

remove duplicate output target for addons/xbmc.json/addon.xml

Motivation and Context

see #15008

How Has This Been Tested?

only quickly on ubuntu. I'm not 100% certain this does not have an side effects...

Screenshots (if appropriate):

Types of change

• Bug fix (non-breaking change which fixes an issue)
• Clean up (non-breaking change which removes non-working, unmaintained functionality)
• Improvement (non-breaking change which improves existing functionality)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that will cause existing functionality to change)
• Cosmetic change (non-breaking change that doesn't touch code)
• None of the above (please explain below)

Checklist:

• My code follows the Code Guidelines of this project
• My change requires a change to the documentation, either Doxygen or wiki
• I have updated the documentation accordingly
• I have read the Contributing document
• I have added tests to cover my change
• All new and existing tests passed

[wsnipex]

updated

[wsnipex]

jenkins build this please

[MilhouseVH]

Tested this with LibreELEC and it's all good with the addition of the fixup commit (xbmc.json/addon.xml isn't installed without the fixup commit). Thanks @wsnipex

[wsnipex]

jenkins build this please

[candrews]

Can this please be considered for Kodi 18?

[wsnipex]

I'd like confirmation that it doesn't somehow break windows first

[candrews]

On that note, should Travis and/or Appveyor be configured to use ninja?

Also, is Travis still used? Travis seems to be disabled for xbmc/xbmc, and when I run it on my own, the build fails due to missing flatbuffers. (If it isn't used, can .travis.yml be deleted to eliminate confusion?)

[DaveTBlake]

I'd like confirmation that it doesn't somehow break windows first

Seems fine @wsnipex ran a Windows x64 build and JSON commands were working as expected.

[gentoo-junkie]

Hi, could you please merge into feature_python3 branch and I will test it there.

[Edit] I patched my local copy of feature_python3 branch with your commit and it built successfully.

[fritsch]

Just cherry-pick it ...

Edit: Did not see your Edit