Remove unnecessary 'extern's.

Change-Id: Iba2b3fb6ff88e504f1657b915120ae43d58a1e03
diff --git a/libc/include/sys/utsname.h b/libc/include/sys/utsname.h
index d54a994..b3856a7 100644
--- a/libc/include/sys/utsname.h
+++ b/libc/include/sys/utsname.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_UTSNAME_H_
 #define _SYS_UTSNAME_H_
 
@@ -43,7 +44,7 @@
     char  domainname[SYS_NMLN];
 };
 
-extern int uname(struct utsname *);
+int uname(struct utsname*);
 
 __END_DECLS