Revert "igb: Disable threaded IRQ for igb_msix_other"

Revert "igb: Disable threaded IRQ for igb_msix_other"

This reverts commit 338c4d3902feb5be49bfda530a72c7ab860e2c9f.

Sebastian noticed the ISR indirectly acquires spin_locks, which are
sleeping locks under PREEMPT_RT, which leads to kernel splats.

Fixes: 338c4d3902feb ("igb: Disable threaded IRQ for igb_msix_other")
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://patch.msgid.link/20241106111427.7272-1-wander@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>