MCU_Microchip_PIC16: Add PIC16F15254, PIC16F15255, PIC16F15256
Datasheets:
https://ww1.microchip.com/downloads/aemDocuments/documents/MCU08/ProductDocuments/DataSheets/PIC16F15254-55-Microcontroller-Data-Sheet-40002324.pdf
https://ww1.microchip.com/downloads/aemDocuments/documents/MCU08/ProductDocuments/DataSheets/PIC16F15256-74-75-76-Microcontroller-Data-Sheet-40002305.pdf
