[ruby-cvs:65488] hsbt:r58316 (trunk): Fix a typo.

[hsbt at ruby-lang.org]

hsbt	2017-04-11 21:19:05 +0900 (Tue, 11 Apr 2017)

  New Revision: 58316

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=58316

  Log:
    Fix a typo.
    
      Patch by @voxik. [fix GH-1581]

  Modified files:
    trunk/ext/etc/etc.gemspec