cc/gcc: add option to compile against static libstdc++, for gcc-4.4 and newer

Idea and know-how taken from CodeSourcery build script.

Normal build:
$ ldd arm-unknown-linux-uclibcgnueabi-gcc
linux-gate.so.1 => (0xb77f3000)
libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0xb76e8000)
libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb75a1000)
libm.so.6 => /lib/i686/cmov/libm.so.6 (0xb757a000)
/lib/ld-linux.so.2 (0xb77f4000)
libgcc_s.so.1 => /lib/libgcc_s.so.1 (0xb755c000)

CC_STATIC_LIBSTDCXX=y:
$ ldd arm-unknown-linux-uclibcgnueabi-gcc
linux-gate.so.1 => (0xb7843000)
libc.so.6 => /lib/i686/cmov/libc.so.6 (0xb76e6000)
/lib/ld-linux.so.2 (0xb7844000)

I made CC_STATIC_LIBSTDCXX default=y since I think
it is always desirable.

Signed-off-by: Johannes Stezenbach <js@sig21.net>

 diff -durN glibc-2.6.1.orig/glibc-ports-2.6.1/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h glibc-2.6.1/glibc-ports-2.6.1/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h

 --- glibc-2.6.1.orig/glibc-ports-2.6.1/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h	2005-11-16 20:22:59.000000000 +0100

 +++ glibc-2.6.1/glibc-ports-2.6.1/sysdeps/unix/sysv/linux/arm/nptl/sysdep-cancel.h	2007-09-06 13:53:16.000000000 +0200

 @@ -126,3 +126,9 @@

  # define NO_CANCELLATION 1

  #endif

 +

 +#ifndef __ASSEMBLER__

 +# define RTLD_SINGLE_THREAD_P \

 +  __builtin_expect (THREAD_GETMEM (THREAD_SELF, \

 +                   header.multiple_threads) == 0, 1)

 +#endif