I need load capacitors on crystal?
Since the load capacitance required for the crystal and the ICS501A datasheet indicates that zero is required for a 12pF crystal you don't actually need any additional capacitance.

However I would put the locations for the capacitors on the PCB but leave them unstuffed (i.e. don't populate any capacitors).  If for some reason you do need extra capacitance or you have to change your crystal supplier to one that needs more capacitance then you are covered without having to spin the PCB.

The sort of problems you might have is that the frequency is slightly incorrect (eg a bit high) or the oscillator does not start reliably.  In those cases you may need to experiment with adding capacitance.