platform/rdv1: do not explicitly specify the yml file

The yml file need not be explicitly specified as a model parameter for
the rdv1 platform. So remove the use of model parameter that is used to
specify the name of the yml file.

Signed-off-by: Thomas Abraham <thomas.abraham@arm.com>
Change-Id: If3e516a4580fc216ad3cb10f4fe3a8082f96a4fd