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>

 Enable using a shell other than bash.

 Courtesy "Martin Guy" <martinwguy@yahoo.it>

 http://sourceware.org/ml/crossgcc/2008-08/msg00037.html

 --- binutils-2.18.orig/ld/genscripts.sh	2007-08-12 20:00:07.000000000 +0100

 +++ binutils-2.18/ld/genscripts.sh	2008-08-25 16:09:54.000000000 +0100

 @@ -398,9 +398,11 @@

      . $em_script

      em_script=$current_script

    }

 -  fragment()

 +  

 +  alias fragment='em_lineno=$LINENO; fragment_em'

 +  fragment_em()

    {

 -    local lineno=$[${BASH_LINENO[0]} + 1]

 +    local lineno=$[$em_lineno + 1]

      echo >> e${EMULATION_NAME}.c "#line $lineno \"$em_script\""

      cat >> e${EMULATION_NAME}.c

    }