ARM: dts: Include exynos5250-pinctrl after the nodes were defined for exynos5250

The dtc compiler combines all the defined nodes that have the same path
so a device node definition can be in one file and later be extended in
another one.

That's the case of the Exynos5250 pinctrl device nodes that are defined
in the exynos5250.dtsi file and extended in exynos5250-pinctrl.dtsi.

But since the exynos5250.dtsi file includes the exynos5250-pinctrl.dtsi
before the pinctrl device nodes are actually defined, the definition of
the pinctrl device nodes happens in exynos5250-pinctrl.dtsi and are
extended in exynos5250.dtsi.

That is the opposite of the original intention so even when there is no
difference in practice, the exynos5250-pinctrl.dtsi include should be
moved at the end of the exynos5250.dtsi file after the pinctrl device
nodes have been already defined.

This will also allow to later change the exynos5250-pinctrl.dtsi file
to use labels instead of full paths to extend the pinctrl nodes. Since
keeping the include at the top, would cause a dtc build error due the
pinctrl labels not being defined yet.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>