binman: Drop unnecessary debug handling

The -D option enables debug mode, but we only need to add -D to the
command line once. Drop the duplicate code. Also drop the comment about
enabling debugging since this can be done with -D.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/binman/binman.py b/tools/binman/binman.py
index 05aeaec..bab9882 100755
--- a/tools/binman/binman.py
+++ b/tools/binman/binman.py
@@ -71,8 +71,6 @@
     sys.argv = [sys.argv[0]]
     if debug:
         sys.argv.append('-D')
-    if debug:
-        sys.argv.append('-D')
 
     # Run the entry tests first ,since these need to be the first to import the
     # 'entry' module.
@@ -151,9 +149,6 @@
     """
     ret_code = 0
 
-    # For testing: This enables full exception traces.
-    #options.debug = True
-
     if not options.debug:
         sys.tracebacklimit = 0