powerpc/mpc85xx: Cleanup license header in source files

Fix the license header introduced by the following patches

Add TWR-P10xx board support
Add T4240EMU target
IDT8T49N222A configuration code
Add C29x SoC support
Add support for C29XPCIE board

Signed-off-by: York Sun <yorksun@freescale.com>
diff --git a/board/freescale/p1_twr/Makefile b/board/freescale/p1_twr/Makefile
index fb29b14..915b9bc 100644
--- a/board/freescale/p1_twr/Makefile
+++ b/board/freescale/p1_twr/Makefile
@@ -1,24 +1,7 @@
 #
 # Copyright 2013 Freescale Semiconductor, Inc.
 #
-# See file CREDITS for list of people who contributed to this
-# project.
-#
-# 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; either version 2 of
-# the License, or (at your option) any later version.
-#
-# 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+
 
 include $(TOPDIR)/config.mk