Function will read PBA Block from Shadow RAM and return it in a string format.

Change-ID: I4ee7059f6e21bd0eba38687da15e772e0b4ab36e
Signed-off-by: NKamil Krawczyk <kamil.krawczyk@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>