m68k: Fix off-by-one in m68k_setup_user_interrupt()

commit 69961c3752 ("[PATCH] m68k/Atari:
Interrupt updates") added a BUG_ON() with an incorrect upper bound
comparison, which causes an early crash on VME boards, where IRQ_USER is
8, cnt is 192 and NR_IRQS is 200.

Reported-by: Stephen N Chivers <schivers@csc.com.au>
Tested-by: Kars de Jong <jongk@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/m68k/kernel/ints.c

@@ -133,7 +133,7 @@ void __init m68k_setup_user_interrupt(unsigned int vec, unsigned int cnt,
 {
 	int i;
 
-	BUG_ON(IRQ_USER + cnt >= NR_IRQS);
+	BUG_ON(IRQ_USER + cnt > NR_IRQS);
 	m68k_first_user_vec = vec;
 	for (i = 0; i < cnt; i++)
 		irq_controller[IRQ_USER + i] = &user_irq_controller;