pinctrl: ocelot: fix system hang on level based interrupts

mainline inclusion
from mainline-v6.12-rc4
commit 93b8ddc54507a227087c60a0013ed833b6ae7d3c
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB2YX2
CVE: CVE-2024-50196

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=93b8ddc54507a227087c60a0013ed833b6ae7d3c



--------------------------------

The current implementation only calls chained_irq_enter() and
chained_irq_exit() if it detects pending interrupts.

```
for (i = 0; i < info->stride; i++) {
	uregmap_read(info->map, id_reg + 4 * i, &reg);
	if (!reg)
		continue;

	chained_irq_enter(parent_chip, desc);
```

However, in case of GPIO pin configured in level mode and the parent
controller configured in edge mode, GPIO interrupt might be lowered by the
hardware. In the result, if the interrupt is short enough, the parent
interrupt is still pending while the GPIO interrupt is cleared;
chained_irq_enter() never gets called and the system hangs trying to
service the parent interrupt.

Moving chained_irq_enter() and chained_irq_exit() outside the for loop
ensures that they are called even when GPIO interrupt is lowered by the
hardware.

The similar code with chained_irq_enter() / chained_irq_exit() functions
wrapping interrupt checking loop may be found in many other drivers:
```
grep -r -A 10 chained_irq_enter drivers/pinctrl
```

Cc: stable@vger.kernel.org
Signed-off-by: Sergey Matsievskiy <matsievskiysv@gmail.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/20241012105743.12450-2-matsievskiysv@gmail.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Conflicts:
	drivers/pinctrl/pinctrl-ocelot.c
[Fix context conflicts.]
Signed-off-by: Zeng Heng <zengheng4@huawei.com>