* include/ruby/ruby.h (RBIGNUM_EMBED_LEN_MAX): Use
  SIZEOF_ACTUAL_BDIGIT instead of SIZEOF_BDIGITS.
  SIZEOF_BDIGITS can be different to sizeof(BDIGIT).



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43829 b2dd03c8-39d4-4d8f-98ff-823fe69b080e