Add PCF8523 RTC
Created by: johnfwhitmore
This is an initial commit of symbol for the PCF8523 RTC, Upload for CI check, but struggling with datasheet entry for base symbol. Earlier today for another component it's flagged as missing but if you add it to the general tab it gets flagged for being included.
Datasheet - https://www.nxp.com/docs/en/data-sheet/PCF8523.pdf