binutils/binutils: do not fwd declare struct stat (2.22).

For canadian cross to host i686-mingw32 fwd declaring
struct stat is not possible.
Instead #include <sys/stat.h>

Signed-off-by: Titus von Boxberg <titus@v9g.de>
Message-Id: <417a15d4277913841ddd.1353100974@tschetwerikow.boxberg.lan>
Patchwork-Id: 199733

 # windows config options

 ## depends on EXPERIMENTAL && ARCH_x86

 ##

 ## select WINDOWS

 ##

 ## help Build a toolchain targeting systems running Windows as host