win32ole.c: suppress warnings

* ext/win32ole/win32ole.c (ole_excepinfo2msg, lcid_installed):
  cast to suppress warnings, SCODE varies on cygwin and mingw.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45684 b2dd03c8-39d4-4d8f-98ff-823fe69b080e