rtl8192se: Fix BUG caused by failure to check skb allocation

commit d90db4b1 upstream.

When downloading firmware into the device, the driver fails to check the
return when allocating an skb. When the allocation fails, a BUG can be
generated, as seen in https://bugzilla.redhat.com/show_bug.cgi?id=771656

.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>