Fix extraneous comma that breaks docbook generation

There is a stray comma in the middle of the help section that changes
the string to a tuple, causing docbook to fail with:

   td.text = "(%s) %s" % (type(option).__name__, option.help.strip())
AttributeError: 'tuple' object has no attribute 'strip'

Change-Id: I8f03801fe5463548e3bba1b13e0370fd30ac9927

cinder/volume/drivers/remotefs.py

@@ -74,7 +74,7 @@
                      'otherwise False. Default is auto.')),
     cfg.StrOpt('nas_share_path',
                default='',
-               help=('Path to the share to use for storing Cinder volumes. ',
+               help=('Path to the share to use for storing Cinder volumes. '
                      'For example:  "/srv/export1" for an NFS server export '
                      'available at 10.0.5.10:/srv/export1 .')),
     cfg.StrOpt('nas_mount_options',