Fix typo in ps.py (#1158)
Fix typo in ps.py (#1158)


yunqu/PYNQ,Xilinx/PYNQ,yunqu/PYNQ,cathalmccabe/PYNQ,cathalmccabe/PYNQ,Xilinx/PYNQ,Xilinx/PYNQ,cathalmccabe/PYNQ,yunqu/PYNQ,schelleg/PYNQ,Xilinx/PYNQ,cathalmccabe/PYNQ,yunqu/PYNQ,Xilinx/PYNQ,schelleg/PYNQ,schelleg/PYNQ,cathalmccabe/PYNQ,cathalmccabe/PYNQ,schelleg/PYNQ,yunqu/PYNQ,schelleg/PYNQ