hwmon: (corsair-cpro) Use a separate buffer for sending commands

[ Upstream commit e0cd85dc ]

Introduce cmd_buffer, a separate buffer for storing only
the command that is sent to the device. Before this separation,
the existing buffer was shared for both the command and the
report received in ccp_raw_event(), which was copied into it.

However, because of hidraw, the raw event parsing may be triggered
in the middle of sending a command, resulting in outputting gibberish
to the device. Using a separate buffer resolves this.

Fixes: 40c3a445

 ("hwmon: add Corsair Commander Pro driver")
Signed-off-by: Aleksa Savic <savicaleksa83@gmail.com>
Acked-by: Marius Zachmann <mail@mariuszachmann.de>
Link: https://lore.kernel.org/r/20240504092504.24158-2-savicaleksa83@gmail.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>