Update espeak-ng to version 1.51 / rev 8 via SR 972411
    
    https://build.opensuse.org/request/show/972411
    by user sebix + dimstar_suse
    - added fix-configure-1171.patch to fix configure step
    - remove no longer needed patches:
      - espeak-ng-1.49.2-fix_no_return_nonvoid-in-configure.patch
      - espeak-ng-1.50-fix_gcc10_no_common.patch
      - espeak-ng-1.50-fix_gcc10_no_common_2.patch
    - update to version 1.51:
     -  Add support for speechPlayer.
     -  Add more tests to check the various parts of espeak-ng.
     -  Various changes to clean up the codebase (Juho Hiltunen)
     -  Remove support for l_length_mods language option
     -  Restructure "option brackets" language option to "brackets" and "bracketsAnnounced"
     -  Restructure "stressLength" and "stressAdd" language option
     -  New Language option: "lowercaseSentence" for ending a sentence if a period is followed by a lower case letter
     -  Add voice variants
     -  Rename zh to cmn (Mandarin)
     -