exynos: sandbox: ti: Add SPDX license identifiers and notes

For some files I neglected to add a license. Rectify this:

arch/arm/dts/exynos4210-pinctrl-uboot.dtsi
arch/arm/dts/exynos4x12-pinctrl-uboot.dtsi
arch/arm/dts/exynos5250-pinctrl-uboot.dtsi
arch/arm/dts/exynos54xx-pinctrl-uboot.dtsi
arch/arm/dts/s5pc100-pinctrl.dtsi
arch/arm/dts/s5pc110-pinctrl.dtsi

This file came from Linux and has no license information there, so add a
comment to that effect:

arch/sandbox/include/asm/bitops.h

This file also came from Linux - presumably someone from TI could add the
license:

include/dt-bindings/pinctrl/omap.h

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Ingrid Viitanen <ingrid.viitanen@nokia.com>
diff --git a/arch/arm/dts/exynos4210-pinctrl-uboot.dtsi b/arch/arm/dts/exynos4210-pinctrl-uboot.dtsi
index f9b61ba..0ff41d0 100644
--- a/arch/arm/dts/exynos4210-pinctrl-uboot.dtsi
+++ b/arch/arm/dts/exynos4210-pinctrl-uboot.dtsi
@@ -2,6 +2,8 @@
  * U-Boot additions to enable a generic Exynos GPIO driver
  *
  * Copyright (c) 2014 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
  */
 
 /{