config: add an option not to remove the destination directory

In certain circumstances, removing the destination/installation directory
is a bad idea. For example, when the build environment is already taking
care of sanitising the build tree, and pre-installs stuff in there, it is
a very bad idea to remove the destination directory.

This happens now in buildroot, as the crostool-NG backend now installs the
toolchain in the common host-tools directory, and pre-install there a few
host-utilities (eg. host-automake and host-gawk).

Provide a config knob to turn on/off the removal of the destination
directory, defaulting to 'y' (previous behavior), and forced to 'n' when
used as a backend.

Reported-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

2007-03-13  Mike Frysinger  <vapier@gentoo.org>

	* sysdeps/unix/sysv/linux/sh/sys/procfs.h: Copy Linux's asm-sh/elf.h types.

--- glibc-2_9/sysdeps/unix/sysv/linux/sh/sys/procfs.h

+++ glibc-2_9/sysdeps/unix/sysv/linux/sh/sys/procfs.h

@@ -29,10 +29,19 @@

 #include <sys/types.h>

 #include <sys/ucontext.h>

 #include <sys/user.h>

-#include <asm/elf.h>

 __BEGIN_DECLS

+/*

+ * ELF register definitions...

+ */

+typedef unsigned long elf_greg_t;

+

+#define ELF_NGREG (sizeof (struct pt_regs) / sizeof(elf_greg_t))

+typedef elf_greg_t elf_gregset_t[ELF_NGREG];

+

+typedef struct user_fpu_struct elf_fpregset_t;

+

 struct elf_siginfo

   {

     int si_signo;			/* Signal number.  */