Coding style cleanup

Fix the following issues reported by pylint:

C0321: More than one statement on a single line
W0622: Redefining built-in 'name'
W0612: Unused variable 'name'
W0613: Unused argument 'name'
W0102: Dangerous default value 'value' as argument
W0105: String statement has no effect

Also fixed a few cases of inconsistent indentation.

Change-Id: Ie0db839e7c57d576cff12d8c055fe87030d00744
diff --git a/subcmds/forall.py b/subcmds/forall.py
index 9436f4e..76a0268 100644
--- a/subcmds/forall.py
+++ b/subcmds/forall.py
@@ -208,7 +208,6 @@
             return self.fd.fileno()
 
         empty = True
-        didout = False
         errbuf = ''
 
         p.stdin.close()
@@ -220,7 +219,7 @@
           fcntl.fcntl(s.fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)
 
         while s_in:
-          in_ready, out_ready, err_ready = select.select(s_in, [], [])
+          in_ready, _out_ready, _err_ready = select.select(s_in, [], [])
           for s in in_ready:
             buf = s.fd.read(4096)
             if not buf:
@@ -229,9 +228,7 @@
               continue
 
             if not opt.verbose:
-              if s.fd == p.stdout:
-                didout = True
-              else:
+              if s.fd != p.stdout:
                 errbuf += buf
                 continue