[MIPS] Fix do_default_vi to use get_irq_regs to get the irq register ptr.

Harmless bug because this function is only called in case of another
kernel bug anyway which is also why this was missed for so long.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/traps.c

@@ -927,9 +927,9 @@ asmlinkage void do_reserved(struct pt_regs *regs)
 	      (regs->cp0_cause & 0x7f) >> 2);
 }
 
-static asmlinkage void do_default_vi(struct pt_regs *regs)
+static asmlinkage void do_default_vi(void)
 {
-	show_regs(regs);
+	show_regs(get_irq_regs());
 	panic("Caught unexpected vectored interrupt.");
 }