arm/dts: Cleanup regulator naming and remove @0,1

regulators do not have a 'reg' property, hence the regulator@0,
regulator@1 do not make sense. get rid of it.

Reported-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>