[bug report] libertas_tf: don't defer firmware loading until start()

[Dan Carpenter]

Hello Lubomir Rintel,

This is a semi-automatic email about new static checker warnings.

The patch baa0280f08c7: "libertas_tf: don't defer firmware loading 
until start()" from Feb 20, 2019, leads to the following Smatch 
complaint:

    drivers/net/wireless/marvell/libertas_tf/if_usb.c:256 if_usb_disconnect()
    warn: variable dereferenced before check 'priv' (see line 254)

drivers/net/wireless/marvell/libertas_tf/if_usb.c
   253  
   254          if_usb_reset_device(priv);
                                    ^^^^^
The patch introduces a new dereference (inside the function).

   255  
   256          if (priv)
                    ^^^^
Old code assumes "priv" could be NULL.

   257                  lbtf_remove_card(priv);
   258  

regards,
dan carpenter