patman: Drop tools.ToChar() and ToChars()

This is useful anymore, since we always want to call chr() in Python 3.
Drop it and adjust callers to use chr().

Also drop ToChars() which is no-longer used.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/patman/tools.py

@@ -423,29 +423,6 @@ def GetBytes(byte, size):
     """
     return bytes([byte]) * size
 
-def ToChar(byte):
-    """Convert a byte to a character
-
-    This is useful because in Python 2 bytes is an alias for str, but in
-    Python 3 they are separate types. This function converts an ASCII value to
-    a value with the appropriate type in either case.
-
-    Args:
-        byte: A byte or str value
-    """
-    return chr(byte) if type(byte) != str else byte
-
-def ToChars(byte_list):
-    """Convert a list of bytes to a str/bytes type
-
-    Args:
-        byte_list: List of ASCII values representing the string
-
-    Returns:
-        string made by concatenating all the ASCII values
-    """
-    return ''.join([chr(byte) for byte in byte_list])
-
 def ToBytes(string):
     """Convert a str type into a bytes type