net: ionic: Replace in_interrupt() usage.

The in_interrupt() usage in this driver tries to figure out which context
may sleep and which context may not sleep. in_interrupt() is not really
suitable as it misses both preemption disabled and interrupt disabled
invocations from task context.

Conditionals like that in driver code are frowned upon in general because
invocations of functions from invalid contexts might not be detected
as the conditional papers over it.

ionic_lif_addr() and _ionoc_lif_rx_mode() can be called from:

 1) ->ndo_set_rx_mode() which is under netif_addr_lock_bh()) so it must not
    sleep.

 2) Init and setup functions which are in fully preemptible task context.

ionic_link_status_check_request() has two call paths:

 1) NAPI which obviously cannot sleep

 2) Setup which is again fully preemptible task context

Add arguments which convey the execution context to the affected functions
and let the callers provide the context instead of letting the functions
deduce it.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>