MIPS: Remove repetitive increase irq_err_count

commit 979934da9e ("[PATCH] mips: update IRQ handling for vr41xx") added
a function irq_dispatch, and it'll increase irq_err_count when the get_irq
callback returns a negative value, but increase irq_err_count in get_irq
was not removed.

And also, modpost complains once gpio-vr41xx drivers become modules.
  ERROR: modpost: "irq_err_count" [drivers/gpio/gpio-vr41xx.ko] undefined!

So it would be a good idea to remove repetitive increase irq_err_count in
get_irq callback.

Fixes: 27fdd325da ("MIPS: Update VR41xx GPIO driver to use gpiolib")
Fixes: 979934da9e ("[PATCH] mips: update IRQ handling for vr41xx")
Reported-by: k2ci <kernel-bot@kylinos.cn>
Signed-off-by: huhai <huhai@kylinos.cn>
Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/vr41xx/common/icu.c

@@ -640,8 +640,6 @@ static int icu_get_irq(unsigned int irq)
 
 	printk(KERN_ERR "spurious ICU interrupt: %04x,%04x\n", pend1, pend2);
 
-	atomic_inc(&irq_err_count);
-
 	return -1;
 }
 

drivers/gpio/gpio-vr41xx.c

@@ -217,8 +217,6 @@ static int giu_get_irq(unsigned int irq)
 	printk(KERN_ERR "spurious GIU interrupt: %04x(%04x),%04x(%04x)\n",
 	       maskl, pendl, maskh, pendh);
 
-	atomic_inc(&irq_err_count);
-
 	return -EINVAL;
 }