Additional Constructor for ACCL XRT Driver

[Mellich]

In the XRT driver, the ACCL constructor currently requires the user to give the cclo and control kernel as xrt::ip and xrt::kernel objects. But in some cases it may be easier for the user to assume default names for these kernels to allow reduction of the code required for initialization.

Therefore, an additional ACCL constructor taking the xrt::uuid instead of the kernels could be provided. The instantiation of the kernels is moved to the constructor itself. Optionally, the kernel names may be given as std::strings to the constructor.