ARM: dts: k2*: Rename the k2* files to keystone-k2* files

ARM: dts: k2*: Rename the k2* files to keystone-k2* files

As reported in [1], rename the k2* dts files to keystone-* files
this will force consistency throughout.

Script for the same (and hand modified for Makefile and MAINTAINERS
files):
for i in arch/arm/boot/dts/k2*
do
	b=`basename $i`;
	git mv $i arch/arm/boot/dts/keystone-$b;
	sed -i -e "s/$b/keystone-$b/g" arch/arm/boot/dts/*[si]
done

NOTE: bootloaders that depend on older dtb names will need to be
updated as well.

[1] http://marc.info/?l=linux-arm-kernel&m=145637407804754&w=2

Reported-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>