Add support for generating DTS from Vivado

This patch ensure that only C_ parameters are generated.
Vivado add also parameters without C_ prefix which
can be ignored.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Add support for generating DTS from Vivado - Microblaze

Support new mig_7series memory controller,
axi_crossbar bus and renamed axi_ethernet_buffer IP.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>