net/mlx5: Allow the throttle mechanism to be more dynamic

Previously, throttle commands were identified and limited based on
opcode. These commands were limited to half the command slots using a
semaphore, and callback commands checked the opcode to determine
semaphore release.

To allow exceptions, we introduce a variable to indicate when the
throttle lock is held. This allows scenarios where throttle commands
are not limited. Callback functions use this variable to determine
if the throttle semaphore needs to be released.

This patch contains no functional changes. It's a preparation for the
next patch.

Signed-off-by: Chiara Meiohas <cmeiohas@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Link: https://patch.msgid.link/055d975edeb816ac4c0fd1e665c6157d11947d26.1740574103.git.leon@kernel.org


Signed-off-by: Leon Romanovsky <leon@kernel.org>