net: txgbe: rework service event handling

net: txgbe: rework service event handling

Convert to use test_and_clear_bit() for link event subtasks. Only re-arm
the WX_FLAG_NEED_MODULE_RESET flag when module is absent. Unsupported or
invalid modules no longer cause the service task to continuously retry
module identification.

Additionally, explicitly cancel service_task during device teardown to
ensure no pending asynchronous service work survives after the device
has entered the DOWN state.

Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Link: https://patch.msgid.link/20260525100543.27140-4-jiawenwu@trustnetic.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>