net/mlx5: HWS, Fix pattern destruction in mlx5hws_pat_get_pattern error path

net/mlx5: HWS, Fix pattern destruction in mlx5hws_pat_get_pattern error path

In mlx5hws_pat_get_pattern(), when mlx5hws_pat_add_pattern_to_cache()
fails, the function attempts to clean up the pattern created by
mlx5hws_cmd_header_modify_pattern_create(). However, it incorrectly
uses *pattern_id which hasn't been set yet, instead of the local
ptrn_id variable that contains the actual pattern ID.

This results in attempting to destroy a pattern using uninitialized
data from the output parameter, rather than the valid pattern ID
returned by the firmware.

Use ptrn_id instead of *pattern_id in the cleanup path to properly
destroy the created pattern.

Fixes: aefc15a0fa1c ("net/mlx5: HWS, added modify header pattern and args handling")
Signed-off-by: Lama Kayal <lkayal@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Link: https://patch.msgid.link/20250825143435.598584-5-mbloch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>