* re.c (rb_memsearch_ss): Apply performance improvement to short
  byte array search for platforms without memmem(3).
  [Feature #6311] [ruby-dev:45530]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37793 b2dd03c8-39d4-4d8f-98ff-823fe69b080e