rtl8192se: Fix BUG caused by failure to check skb allocation

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 <[e-mail]>
Cc: Stable <[e-mail]>
Signed-off-by: John W. Linville <[e-mail]>

drivers/net/wireless/rtlwifi/rtl8192se/fw.c

···
 		/* Allocate skb buffer to contain firmware */
 		/* info and tx descriptor info. */
 		skb = dev_alloc_skb(frag_length);
+		if (!skb)
+			return false;
 		skb_reserve(skb, extra_descoffset);
 		seg_ptr = (u8 *)skb_put(skb, (u32)(frag_length -
 					extra_descoffset));
···
 
 	len = _rtl92s_get_h2c_cmdlen(MAX_TRANSMIT_BUFFER_SIZE, 1, &cmd_len);
 	skb = dev_alloc_skb(len);
+	if (!skb)
+		return false;
 	cb_desc = (struct rtl_tcb_desc *)(skb->cb);
 	cb_desc->queue_index = TXCMD_QUEUE;
 	cb_desc->cmd_or_init = DESC_PACKET_TYPE_NORMAL;