staging: r8188eu: Remove redundant code from rtw_free_netdev()

In rtw_free_netdev() there are two redundant tests. The first checks for
a valid pointer to a "struct net_device". This pointer is the argument
of rtw_free_netdev(). The two callers of this function already test this
parameter immediatelly before the calls. The second checks for a valid
pointer to a "struct rtw_netdev_priv_indicator". This pointer is always
valid and, even if it were not, vfree() is a no-op on NULL pointers.

Therefore the above-mentioned two "if" statements are unnecessary and
redundant. For this reason, remove these two tests.

After removing these tests there is no more need of the "RETURN" label.
Therefore, remove also the "RETURN" label.

Cc: Pavel Skripkin <[e-mail]>
Cc: Martin Kaiser <[e-mail]>
Signed-off-by: Fabio M. De Francesco <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/staging/r8188eu/os_dep/osdep_service.c

···
 {
 	struct rtw_netdev_priv_indicator *pnpi;
 
-	if (!netdev)
-		goto RETURN;
-
 	pnpi = netdev_priv(netdev);
-
-	if (!pnpi->priv)
-		goto RETURN;
 
 	vfree(pnpi->priv);
 	free_netdev(netdev);
-
-RETURN:
-	return;
 }
 
 int rtw_change_ifname(struct adapter *padapter, const char *ifname)