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>
diff --git a/tools/dtoc/fdt.py b/tools/dtoc/fdt.py
index cb365ca..4a78c73 100644
--- a/tools/dtoc/fdt.py
+++ b/tools/dtoc/fdt.py
@@ -87,9 +87,9 @@
             return Type.STRING, [s.decode() for s in strings[:-1]]
     if size % 4:
         if size == 1:
-            return Type.BYTE, tools.ToChar(data[0])
+            return Type.BYTE, chr(data[0])
         else:
-            return Type.BYTE, [tools.ToChar(ch) for ch in list(data)]
+            return Type.BYTE, [chr(ch) for ch in list(data)]
     val = []
     for i in range(0, size, 4):
         val.append(data[i:i + 4])
@@ -152,9 +152,9 @@
                 if type(self.value) == list:
                     new_value = []
                     for val in self.value:
-                        new_value += [tools.ToChar(by) for by in val]
+                        new_value += [chr(by) for by in val]
                 else:
-                    new_value = [tools.ToChar(by) for by in self.value]
+                    new_value = [chr(by) for by in self.value]
                 self.value = new_value
             self.type = newprop.type
 
diff --git a/tools/dtoc/test_fdt.py b/tools/dtoc/test_fdt.py
index 10e7f33..dc6943f 100755
--- a/tools/dtoc/test_fdt.py
+++ b/tools/dtoc/test_fdt.py
@@ -46,7 +46,7 @@
     # Add 12, which is sizeof(struct fdt_property), to get to start of data
     offset = prop.GetOffset() + 12
     data = dtb.GetContents()[offset:offset + len(prop.value)]
-    return prop, [tools.ToChar(x) for x in data]
+    return prop, [chr(x) for x in data]
 
 
 class TestFdt(unittest.TestCase):
diff --git a/tools/patman/tools.py b/tools/patman/tools.py
index 7cd5803..00c7013 100644
--- a/tools/patman/tools.py
+++ b/tools/patman/tools.py
@@ -423,29 +423,6 @@
     """
     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