Remove an old function we don't use any more

dool

@@ -1785,14 +1785,6 @@ def ticks():
             if l[0] == 'btime':
                 return time.time() - int(l[1])
 
-def improve(devname):
-    "Improve a device name"
-    if devname.startswith('/dev/mapper/'):
-        devname = devname.split('/')[3]
-    elif devname.startswith('/dev/'):
-        devname = devname.split('/')[2]
-    return devname
-
 def dopen(filename):
     "Open a file for reuse, if already opened, return file descriptor"
     global fds