ipsocket.c: fix merge miss
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50405 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
ipsocket.c: fix merge miss
variable name by merge miss. [ruby-core:68531] [Bug #10975]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@50405 b2dd03c8-39d4-4d8f-98ff-823fe69b080e