libc/uClibc: fix building on system with recent glibc

While trying to build a toolchain with ct-ng 1.5.0,
arm-unknown-linux-uclibcgnueabi target,
I get the following error:

[INFO ] Installing C library headers
[EXTRA] Copying sources to build dir
[EXTRA] Applying configuration
[EXTRA] Building headers
[EXTRA] Installing headers
[ERROR] extra/scripts/unifdef.c:209: error: conflicting types for 'getline'
[ERROR] make[2]: *** [extra/scripts/unifdef] Error 1
[ERROR] Build failed in step 'Installing C library headers'

The following patch solves the problem.
(It's a backport of this uClibc commit:
http://git.uclibc.org/uClibc/commit/?id=49e81cada73616864b9b31df0aeb6961c30f5a6e
)

[--SNIP from another mail--]
AFAIK this is a problem since glibc 2.10.

# Binary utilities menu

menu "Binary utilities"

choice

    bool

    prompt "Binary format:"

if ARCH_USE_MMU

config ARCH_BINFMT_ELF

    bool

    prompt "ELF"

    help

      This will make your system build ELF exectubales,

      suitable for architectures with an MMU.

endif # ARCH_USE_MMU

if ! ARCH_USE_MMU

config ARCH_BINFMT_FLAT

    bool

    prompt "Flat"

    help

      This will build flat binaries, suitable for

      MMU-less architectures.

#config ARCH_BINFMT_FDPIC

#    bool

#    prompt "FD_PIC ELF"

#    help

#      This will build FD_PIC ELF binaries, suitable for

#      MMU-less architectures that still require to use

#      shared libraries (FIXME).

endif # ! ARCH_USE_MMU

endchoice

source config/binutils/binutils.in

source config/binutils/elf2flt.in

endmenu