[ruby-cvs:72903] nobu:r65803 (trunk): .travis.yml: do not pass unnecessary warnflags

[nobu at ruby-lang.org]

nobu	2018-11-19 18:42:10 +0900 (Mon, 19 Nov 2018)

  New Revision: 65803

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=65803

  Log:
    .travis.yml: do not pass unnecessary warnflags

  Modified files:
    trunk/.travis.yml