Changes to removed default configuration of including an RTC.
Modified to point at Alpha Data branch.
Removed RTC configuration.
changes to serial port numbering.
Merge branch 'dora' of https://github.com/Alpha-Data-Parallel-Systems-Ltd/meta-xilinx into dora

# By David Dolman
# Via David Dolman
* 'dora' of https://github.com/Alpha-Data-Parallel-Systems-Ltd/meta-xilinx:
  Added initial files to Alpha Data fork of dora meta-xilinx to support the admxrc7z1.

Conflicts:
	conf/machine/boards/admxrc7z1/admxrc7z1.dts
	conf/machine/boards/admxrc7z1/admxrc7z1.dtsi