m58: New files for FreeRTOS support

- Add sbt/hardware tree for SDRDC hardware description when setting up FreeRTOS BSP in
  Xilinx SDK
- SDRDC-AMP BSP for preconfigured Petalinux side of AMP recipe
- Prebuilt FreeRTOS application for testing
m58: DTS and config changes for FreeRTOS AMP