Tools: Fix script logging

Fix issue preventing scripts respecting --log_level argument, by adding
a non-default handler. Also, add script name to log output.

Change-Id: I100a5c29276d362dc38cd6c46f472e5991873293
Signed-off-by: Raef Coles <raef.coles@arm.com>
diff --git a/tools/modules/file_loader.py b/tools/modules/file_loader.py
index 249c93f..aa42140 100644
--- a/tools/modules/file_loader.py
+++ b/tools/modules/file_loader.py
@@ -7,7 +7,7 @@
 
 from cryptography.hazmat.primitives.serialization import load_pem_private_key, Encoding, PublicFormat
 import logging
-logger = logging.getLogger("TF-M")
+logger = logging.getLogger("TF-M.{}".format(__name__))
 from os.path import splitext, isfile
 
 def _load_bin(filepath):