wifi: iwlwifi: Fix error code in iwl_op_mode_dvm_start()
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: Fix error code in iwl_op_mode_dvm_start()
Preserve the error code if iwl_setup_deferred_work() fails. The current code returns ERR_PTR(0) (which is NULL) on this path. I believe the missing error code potentially leads to a use after free involving debugfs.