Fix warning Synth 8-614
Fix warning Synth 8-614

WARNING: [Synth 8-614] signal 'pRst' is read in the process but is not in the sensitivity list [.../src/ClockGen.vhd:97]
Digilent/vivado-library,Digilent/vivado-library,Digilent/vivado-library,Digilent/vivado-library