[tools] host/include/getline.h - Mac OS X 10.7 (Lion) fix

[tools] host/include/getline.h - Mac OS X 10.7 (Lion) fix

Apple has finally updated their version of Libc, and it now includes getline(). \o/

The following patch fixes OpenWRT getline.h to not redefine it for 10.7. The one
caveat is, the includes (at least stdio.h) are needed before the #ifdef so that
__DARWIN_C_LEVEL could be properly defined (it is not a compiler built-in define
like __linux__ or __APPLE__).

This one fixes the host/include/getline.h. The next patch will mend the mkimage
package.

Signed-off-by: Joe Roback <openwrt-devel at roback.cc>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@27916 3c298f89-4303-0410-b956-a3cf2f4a3e73