Update to a hopefully more future proof FSF address

Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/hw/bt.h b/hw/bt.h
index 726905f..4a702ad 100644
--- a/hw/bt.h
+++ b/hw/bt.h
@@ -20,9 +20,7 @@
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
- * MA  02110-1301  USA
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 /* BD Address */