tehuti: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ethernet: use core min/max MTU checking

et131x: min_mtu 64, max_mtu 9216

altera_tse: min_mtu 64, max_mtu 1500

amd8111e: min_mtu 60, max_mtu 9000

bnad: min_mtu 46, max_mtu 9000

macb: min_mtu 68, max_mtu 1500 or 10240 depending on hardware capability

xgmac: min_mtu 46, max_mtu 9000

cxgb2: min_mtu 68, max_mtu 9582 (pm3393) or 9600 (vsc7326)

enic: min_mtu 68, max_mtu 9000

gianfar: min_mtu 50, max_mu 9586

hns_enet: min_mtu 68, max_mtu 9578 (v1) or 9706 (v2)

ksz884x: min_mtu 60, max_mtu 1894

myri10ge: min_mtu 68, max_mtu 9000

natsemi: min_mtu 64, max_mtu 2024

nfp: min_mtu 68, max_mtu hardware-specific

forcedeth: min_mtu 64, max_mtu 1500 or 9100, depending on hardware

pch_gbe: min_mtu 46, max_mtu 10300

pasemi_mac: min_mtu 64, max_mtu 9000

qcaspi: min_mtu 46, max_mtu 1500
- remove qcaspi_netdev_change_mtu as it is now redundant

rocker: min_mtu 68, max_mtu 9000

sxgbe: min_mtu 68, max_mtu 9000

stmmac: min_mtu 46, max_mtu depends on hardware

tehuti: min_mtu 60, max_mtu 16384
- driver had no max mtu checking, but product docs say 16k jumbo packets
are supported by the hardware

netcp: min_mtu 68, max_mtu 9486
- remove netcp_ndo_change_mtu as it is now redundant

via-velocity: min_mtu 64, max_mtu 9000

octeon: min_mtu 46, max_mtu 65370

CC: netdev@vger.kernel.org
CC: Mark Einon <mark.einon@gmail.com>
CC: Vince Bridgers <vbridger@opensource.altera.com>
CC: Rasesh Mody <rasesh.mody@qlogic.com>
CC: Nicolas Ferre <nicolas.ferre@atmel.com>
CC: Santosh Raspatur <santosh@chelsio.com>
CC: Hariprasad S <hariprasad@chelsio.com>
CC: Christian Benvenuti <benve@cisco.com>
CC: Sujith Sankar <ssujith@cisco.com>
CC: Govindarajulu Varadarajan <_govind@gmx.com>
CC: Neel Patel <neepatel@cisco.com>
CC: Claudiu Manoil <claudiu.manoil@freescale.com>
CC: Yisen Zhuang <yisen.zhuang@huawei.com>
CC: Salil Mehta <salil.mehta@huawei.com>
CC: Hyong-Youb Kim <hykim@myri.com>
CC: Jakub Kicinski <jakub.kicinski@netronome.com>
CC: Olof Johansson <olof@lixom.net>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Byungho An <bh74.an@samsung.com>
CC: Girish K S <ks.giri@samsung.com>
CC: Vipul Pandya <vipul.pandya@samsung.com>
CC: Giuseppe Cavallaro <peppe.cavallaro@st.com>
CC: Alexandre Torgue <alexandre.torgue@st.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Wingman Kwok <w-kwok2@ti.com>
CC: Murali Karicheri <m-karicheri2@ti.com>
CC: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tehuti: Move the Tehuti driver

Move the Tehuti driver into drivers/net/ethernet/tehuti/ and
make the necessary Kconfig and Makefile changes.

CC: Alexander Indenbaum <baum@tehutinetworks.net>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>