wifi: mwifiex: Fix memcpy() field-spanning write warning in mwifiex_cmd_802_11_scan_ext()

[ Upstream commit 498365e52bebcbc36a93279fe7e9d6aec8479cee ]

Replace one-element array with a flexible-array member in
`struct host_cmd_ds_802_11_scan_ext`.

With this, fix the following warning:

elo 16 17:51:58 surfacebook kernel: ------------[ cut here ]------------
elo 16 17:51:58 surfacebook kernel: memcpy: detected field-spanning write (size 243) of single field "ext_scan->tlv_buffer" at drivers/net/wireless/marvell/mwifiex/scan.c:2239 (size 1)
elo 16 17:51:58 surfacebook kernel: WARNING: CPU: 0 PID: 498 at drivers/net/wireless/marvell/mwifiex/scan.c:2239 mwifiex_cmd_802_11_scan_ext+0x83/0x90 [mwifiex]

Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Closes: https://lore.kernel.org/linux-hardening/ZsZNgfnEwOcPdCly@black.fi.intel.com/


Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://patch.msgid.link/ZsZa5xRcsLq9D+RX@elsanto


Signed-off-by: Sasha Levin <sashal@kernel.org>