Update alevt to version 1.8.0 / rev 22 via SR 886640
    
    https://build.opensuse.org/request/show/886640
    by user pluskalm + dimstar_suse
     - Fix previous changelog entry
    
    - Update to 1.8.0
      * DVB-T support
      * Increase program table size from 16 to 128
      * Fix crash if no DVB service has Teletext
      * Detect HEVC services for all regions (this fixes HEVC in Germany)
      * Fix 100% cpu use when there is no vbi device
      * Add zvbi support
      * Add support for iso8859-7 (greek)
      * Add support for KOI8-R encoding
      * Support libpng-1.6
    - Update to 1.6.3
      * compilation fix for libpng-1.5, this obsoletes alevt-libpng15.patch
    - Dropped obsoleted alevt-1.6.0-dvb-demux.patch,
      alevt-happy-abuild.diff and alevt-overflow2.diff
      alevt-libpng15.patch
    - Modernized and fixed SPEC file
      * Added working upstream URL
    - Add use-pkgconfig.patch