opencv: fix disting of new header files

Fixes distcheck.
6 jobs for master in 27 minutes and 34 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Preparation
passed #70096
gst indent

00:00:16

passed #70095
manifest

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  Build
passed #70097
build fedora x86_64

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  Test
passed #70098
check fedora

00:14:35

 
  Full Builds
passed #70099
build android arm64 api28

00:03:37

passed #70100
build cerbero fedora x86_64

00:08:52