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.

 Original patch from Gentoo.

 -= BEGIN original header =-

 -= END original header =-

 diff -durN uClibc-0.9.30.orig/libc/inet/resolv.c uClibc-0.9.30/libc/inet/resolv.c

 --- uClibc-0.9.30.orig/libc/inet/resolv.c	2008-11-02 01:25:33.000000000 +0100

 +++ uClibc-0.9.30/libc/inet/resolv.c	2009-02-07 09:57:59.000000000 +0100

 @@ -1788,7 +1788,7 @@

  int gethostent_r(struct hostent *result_buf, char *buf, size_t buflen,

  	struct hostent **result, int *h_errnop)

  {

 -	int ret;

 +	int ret = HOST_NOT_FOUND;

  	__UCLIBC_MUTEX_LOCK(mylock);

  	if (__gethostent_fp == NULL) {