ARM: DT: binding fixup to align with vendor-prefixes.txt (drivers)

[ this is a follow-up to this discussion:
http://archive.arm.linux.org.uk/lurker/message/20130730.230827.a1ceb12a.en.html ]
This patchset renames all uses of "bcm," name bindings to
"brcm," as they were done prior to knowing that brcm had
already been standardized as Broadcom vendor prefix
(in Documentation/devicetree/bindings/vendor-prefixes.txt).
This will not cause any churn on devices because none of
these bindings have made it into production yet.

Signed-off-by: Christian Daudt <csd@broadcom.com>
Acked-by: Stephen Warren <swarren@nvidia.com>