misc: hi6421-spmi-pmic: Use generic_handle_irq_safe().

generic_handle_irq() is invoked from a regular interrupt service
routine. This handler will become a forced-threaded handler on
PREEMPT_RT and will be invoked with enabled interrupts. The
generic_handle_irq() must be invoked with disabled interrupts in order
to avoid deadlocks.

Instead of manually disabling interrupts before invoking use
generic_handle_irq_safe() which can be invoked with enabled and disabled
interrupts.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org> 
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20220211181500.1856198-5-bigeasy@linutronix.de

Author: Sebastian Andrzej Siewior

drivers/misc/hi6421v600-irq.c

@@ -117,16 +117,16 @@ static irqreturn_t hi6421v600_irq_handler(int irq, void *__priv)
 			 * If both powerkey down and up IRQs are received,
 			 * handle them at the right order
 			 */
-			generic_handle_irq(priv->irqs[POWERKEY_DOWN]);
-			generic_handle_irq(priv->irqs[POWERKEY_UP]);
+			generic_handle_irq_safe(priv->irqs[POWERKEY_DOWN]);
+			generic_handle_irq_safe(priv->irqs[POWERKEY_UP]);
 			pending &= ~HISI_IRQ_POWERKEY_UP_DOWN;
 		}
 
 		if (!pending)
 			continue;
 
 		for_each_set_bit(offset, &pending, BITS_PER_BYTE) {
-			generic_handle_irq(priv->irqs[offset + i * BITS_PER_BYTE]);
+			generic_handle_irq_safe(priv->irqs[offset + i * BITS_PER_BYTE]);
 		}
 	}