CVE-2025-71180: counter: interrupt-cnt: Drop IRQF_NO_THREAD flag

In the Linux kernel, the following vulnerability has been resolved:

counter: interrupt-cnt: Drop IRQFNOTHREAD flag

An IRQ handler can either be IRQFNOTHREAD or acquire spinlockt, as CONFIGPROVERAWLOCKNESTING warns: ============================= [ BUG: Invalid wait context ] 6.18.0-rc1+git... #1 ----------------------------- some-user-space-process/1251 is trying to lock: (&counter->eventslistlock){....}-{3:3}, at: counterpushevent [counter] other info that might help us debug this: context-{2:2} no locks held by some-user-space-process/.... stack backtrace: CPU: 0 UID: 0 PID: 1251 Comm: some-user-space-process 6.18.0-rc1+git... #1 PREEMPT Call trace: showstack (C) dumpstacklvl dumpstack lockacquire lockacquire rawspinlockirqsave counterpushevent [counter] interruptcntisr [interruptcnt] handleirqeventpercpu handleirqevent handlesimpleirq handleirqdesc generichandledomainirq gpioirqhandler handleirqdesc generichandledomainirq gichandleirq callonirqstack dointerrupthandler el0interrupt el0irqhandlercommon el0t64irqhandler el0t64irq

... and Sebastian correctly points out. Remove IRQFNOTHREAD as an alternative to switching to rawspinlockt, because the latter would limit all potential nested locks to rawspinlockt only.