* csu/Makefile [$(elf)=yes] (have-initfini): Set to yes.
[$(have-initfini)=yes]: Test this rather than $(elf) for crtstuff.
[start-installed-name-rule]: If this is defined, elide rule for
$(objpfx)$(start-installed-name).
* sysdeps/unix/sysv/sco3.2.4/Makefile [$(subdir)=csu]
(start-installed-rule, start-installed-name-rule): New variables;
specify crt1.o, created by our own rule.
($(objpfx)crt1.o): New rule.
* configure.in: Require autoconf 2.4.2 or later. Change all
AC_CACHE_VAL uses to use new AC_CACHE_CHECK macro instead;
prettify some messages.
[$elf!=yes] (libc_cv_have_initfini): New test for `.init' and `.fini'
sections.
* munch-tmpl.c [HAVE_INITFINI]: Call _init and atexit (_fini) in
this case rather than #ifdef HAVE_ELF.
* config.h.in (HAVE_INITFINI): New macro.