universal binary. replaced --enable-fat-binary option which
didn't work actually.
* configure.in (RUBY_FUNC_ATTRIBUTE): added conditional test.
* configure.in (ac_cv_type_getgroups): decalared because getgroups()
fills rest of the buffer with garbages on Rosetta.
* configure.in (alloca): defines only for powerpc, but always
create empty object to suppress ld warning.
* configure.in (LIBRUBY_DLDFLAGS): set compatibility version with
TEENY.
* configure.in (CFLAGS, LDFLAGS): separates ARCH_FLAG.
* configure.in (arch): renamed to "universal" from "fat".
* Makefile.in (ARCH_FLAG): added.
* include/ruby/defines.h (WORDS_BIGENDIAN): uses
AC_APPLE_UNIVERSAL_BUILD.
* missing/alloca.c (alloca): defines only if C_ALLOCA is defined.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@22106 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
