mimxrt/boards/make-pins.py: Allow empty lines and comments in pins.csv.

ports/mimxrt/boards/make-pins.py

@@ -180,6 +180,12 @@ class Pins(object):
         with open(filename, "r") as csvfile:
             rows = csv.reader(csvfile)
             for row in rows:
+                if len(row) == 0 or row[0].startswith("#"):
+                    # Skip empty lines, and lines starting with "#"
+                    continue
+                if len(row) != 2:
+                    raise ValueError("Expecting two entries in a row")
+
                 pin = self.find_pin_by_name(row[1])
                 if pin and row[0]:  # Only add board pins that have a name
                     self.board_pins.append(NamedPin(row[0], pin.pad, pin.idx))