Debug Plugin: Choose where to read registers from: SPI or AXI Core
- When a device does not have a corresponding xml file, show these options
Debug Plugin: Fix register autoread not working properly
              - when a xml file is not loaded, autoread has no effect
Datafile in: Fix bug that crashes app when loading a .mat file
Also take care of the following "fix-me" left inside the code:
/* need to clean up, huge memory leak occurs here */
Datafile in: swap I/Q for mat files, so things work, and produce
             positive offsets.

Signed-off-by: Robin Getz <Robin.Getz@analog.com>
xmls: Rename ad9361.xml to ad9361-phy.xml
       - this will make the debug plugin load the xml file only for ad9361-phy device
xmls: Add xml files for AXI Core ADC and AXI Core DAC
Debug Plugin: Make sure all mask are unsigned long