libg/eglibc: add updated eglibc 2.15

Includes a patch to remove __builtin_expect test:

In eglibc-2.15, the build breaks in configure while testing
for the existance of __builtin_expect. It fails with newer
versions of gcc.

This patch is a modification of an upstream change in glibc
mainline (to be 2.16) to fix the following error:

[CFG ] checking for __builtin_expect... no
[ERROR] configure: error: support for __builtin_expect needed

http://sourceware.org/git/?p=glibc.git;a=commit;h=3857022a761ea7251f8e5c0e45d382ebc3e34cf9

Signed-off-by: Bryan Hundven <bryanhundven@gmail.com>
[yann.morin.1998@free.fr: coalesce both patches into a single changeset]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>

 --- gcc-4.0.0/boehm-gc/include/gc.h-orig	2005-04-28 22:28:57.000000000 -0500

 +++ gcc-4.0.0/boehm-gc/include/gc.h	2005-04-28 22:30:38.000000000 -0500

 @@ -500,7 +500,7 @@

  #ifdef __linux__

  # include <features.h>

  # if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 1 || __GLIBC__ > 2) \

 -     && !defined(__ia64__)

 +     && !defined(__ia64__) && !defined(__UCLIBC__)

  #   ifndef GC_HAVE_BUILTIN_BACKTRACE

  #     define GC_HAVE_BUILTIN_BACKTRACE

  #   endif