mlx5e: add add missing BH locking around napi_schdule()
It's not correct to call napi_schedule() in pure process
context. Because we use __raise_softirq_irqoff() we require
callers to be in a context which will eventually lead to
softirq handling (hardirq, bh disabled, etc.).
With code as is users will see:
NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!!