usb: Update some EHCI driver licenses to use SPDX

A few drivers still write out the license in full. Fix these.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Marek Vasut <marex@denx.de>
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 774282d..3379c29 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -3,20 +3,7 @@
  * Copyright (c) 2008, Michael Trimarchi <trimarchimichael@yahoo.it>
  * All rights reserved.
  *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation version 2 of
- * the License.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * 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., 59 Temple Place, Suite 330, Boston,
- * MA 02111-1307 USA
+ * SPDX-License-Identifier:	GPL-2.0
  */
 
 #ifndef USB_EHCI_H