Do I need to have both the HDCP 1.4 and HDCP 2.2 cores or is HDCP 2.2 a superset of HDMI 1.4?
In order to support both HDCP 1.4 and HDCP 2.2, you will need to include both IPs.
This is because High-bandwidth Digital Content Protection (HDCP) 1.x and 2.x are 2 different algorithms. HDCP 2.x is a completely different link protection based on AES and is not backward compatible.
For more information, see the overview of HDCP v2.X on Wikipedia.