ARM: dts: realview-pbx: Fix duplicate regulator nodes

There's a bug in dtc in checking for duplicate node names when there's
another section (e.g. "/ { };"). In this case, skeleton.dtsi provides
another section. Upon removal of skeleton.dtsi, the dtb fails to build
due to a duplicate node 'fixedregulator@0'. As both nodes were pretty
much the same 3.3V fixed regulator, it hasn't really mattered. Fix this
by renaming the nodes to something unique. In the process, drop the
unit-address which shouldn't be present wtihout reg property.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Olof Johansson <olof@lixom.net>