rescue Errno::EPROTOTYPE in FTPTest#test_list_read_timeout_exceeded.

Errno::EPROTOTYPE is sometimes raised on Mac OS X 10.10.
[ruby-core:78066] [Bug #12914]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56882 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/net/ftp/test_ftp.rb

@@ -421,7 +421,7 @@ class FTPTest < Test::Unit::TestCase
           end
           conn.print(l, "\r\n")
         end
-      rescue Errno::EPIPE
+      rescue Errno::EPIPE, Errno::EPROTOTYPE
       ensure
         assert_nil($!)
         conn.close