Add configuration files/dtses for mini u-boot configuration
which runs on smaller footprint of internal memory. This
configuration has only required qspi flash support and it
uses DCC as serial.
Signed-off-by: Siva Durga Prasad Paladugu <siva.durga.paladugu@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>