style: remove trailing whitespace

Result of running 'hg m5style --skip-all --fix-white -a'.

util/qdo

@@ -97,11 +97,11 @@ class Shell(pexpect.spawn):
 
     def __init__(self, cmd):
         # initialize base pexpect.spawn object
-	try:
+        try:
             pexpect.spawn.__init__(self, cmd)
-	except pexpect.ExceptionPexpect, exc:
-	    print "%s:" % progname, exc
-	    sys.exit(1)
+        except pexpect.ExceptionPexpect, exc:
+            print "%s:" % progname, exc
+            sys.exit(1)
         # full_output accumulates the full output of the session
         self.full_output = ""
         self.quick_timeout = 15