* configure.host: New file.
* configure.tgt: New file.
* aclocal.m4: New file.
* configure: New file, built by autoconf.
* acconfig.h: New file.
* config.h.in: New file, built by autoheader.
* sysdep.h: New file.
* ld.h: Incorporate old contents of config.h.
* config.h: Remove.
* Makefile.in: Various changes for new configure script. Also:
(CC_FOR_BUILD): Remove.
(ldmain.o): Don't bother to ensure that EMUL is non-empty.
(dep.sed): Use @SRCDIR@, not @srcdir@.
* dep-in.sed: Use @SRCDIR@, not @srcdir@.
* genscripts.sh: Create ldscripts if it does not exist.
* ldemul.c, lexsup.c, mpw-emipsidt.c: Don't include "config.h".
* mpw-esh.c, emultemp/*.em: Likewise.
* ldmain.c: Likewise. Include <ctype.h>. Don't try to set
HAVE_SBRK here.
* config/*.mt, config/*.mh: Remove.