ARM: dts: bcm: fix msi-controller name and unit address

The unit address for the msi controller is not valid as there is no reg
property, so remove it. Also, msi-controller is the preferred node name.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Jon Mason <jonmason@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Acked-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>