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-2.10.1.orig/sysdeps/sh/sh4/fpu/fpu_control.h glibc-2.10.1/sysdeps/sh/sh4/fpu/fpu_control.h

 --- glibc-2.10.1.orig/sysdeps/sh/sh4/fpu/fpu_control.h	2001-07-06 06:56:04.000000000 +0200

 +++ glibc-2.10.1/sysdeps/sh/sh4/fpu/fpu_control.h	2009-11-13 00:51:26.000000000 +0100

 @@ -45,6 +45,7 @@

  #define _FPU_GETCW(cw) __asm__ ("sts fpscr,%0" : "=r" (cw))

  #if defined __GNUC__

 +extern void __set_fpscr(unsigned long);

  #define _FPU_SETCW(cw) __set_fpscr ((cw))

  #else

  #define _FPU_SETCW(cw) __asm__ ("lds %0,fpscr" : : "r" (cw))