[navicli] catch exception if input is unreadable

CLARiiON SP IP Address or [Enter] to exit: Traceback (most recent call last):
  File "/usr/sbin/sosreport", line 25, in <module>
    main(sys.argv[1:])
  File "/usr/lib/python2.7/site-packages/sos/sosreport.py", line 1408, in main
    sos.execute()
  File "/usr/lib/python2.7/site-packages/sos/sosreport.py", line 1387, in execute
    self.setup()
  File "/usr/lib/python2.7/site-packages/sos/sosreport.py", line 1117, in setup
    plug.setup()
  File "/usr/lib/python2.7/site-packages/sos/plugins/navicli.py", line 72, in setup
    ans = input("CLARiiON SP IP Address or [Enter] to exit: ")
EOFError: EOF when reading a line

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>