Bluetooth: fix unaligned access to l2cap conf data

In function l2cap_get_conf_opt() and l2cap_add_conf_opt() the address of
opt->val sometimes is not at the edge of 2-bytes/4-bytes, so 2-bytes/4 bytes
access will cause data misalignment exeception. Use get_unaligned_le16/32
and put_unaligned_le16/32 function to avoid data misalignment execption.

Signed-off-by: steven miao <[e-mail]>
Signed-off-by: Mike Frysinger <[e-mail]>
Acked-by: Marcel Holtmann <[e-mail]>
Signed-off-by: Gustavo F. Padovan <[e-mail]>

net/bluetooth/l2cap.c

···
 		break;
 
 	case 2:
-		*val = __le16_to_cpu(*((__le16 *) opt->val));
+		*val = get_unaligned_le16(opt->val);
 		break;
 
 	case 4:
-		*val = __le32_to_cpu(*((__le32 *) opt->val));
+		*val = get_unaligned_le32(opt->val);
 		break;
 
 	default:
···
 		break;
 
 	case 2:
-		*((__le16 *) opt->val) = cpu_to_le16(val);
+		put_unaligned_le16(cpu_to_le16(val), opt->val);
 		break;
 
 	case 4:
-		*((__le32 *) opt->val) = cpu_to_le32(val);
+		put_unaligned_le32(cpu_to_le32(val), opt->val);
 		break;
 
 	default: