stm32/boards: Support 'FDCAN' in board pin CSVs.

Previously micros with the 'FDCAN' peripheral (as opposed to the older
'CAN' peripheral) needed to rename these pins in the CSVs for the CAN
driver to work.

The following CSVs in MicroPython still had FDCAN in them:

    $ rg -t csv -l FDCAN boards
    boards/stm32h7b3_af.csv
    boards/stm32h743_af.csv
    boards/stm32h573_af.csv
    boards/stm32h723_af.csv
    boards/stm32g0b1_af.csv

Confirmed that this allows CAN to work on NUCLEO_H723ZG board, and that at
least one board based on each of the other chips can still compile. Some of
these boards could possibly have MICROPY_HW_ENABLE_CAN set and work, now.

Signed-off-by: Angus Gratton <angus@redyak.com.au>

Author: projectgus

ports/stm32/boards/make-pins.py

@@ -122,6 +122,9 @@ def add_af(self, af_idx, af_name, af):
                 if af_ext:
                     af_pin = "EXT" + af_pin
 
+                # Special case: FDCAN peripheral is named CAN in MicroPython, same as bxCAN
+                af_fn = af_fn.replace("FDCAN", "CAN")
+
                 af_supported = af_fn in SUPPORTED_AF and af_pin in SUPPORTED_AF[af_fn]
 
                 self._afs.append(PinAf(af_idx, af_fn, af_unit, af_pin, af_supported, af_name))