frv: Remove stale irq_chip.end

irq_chip.end got obsolete with the removal of __do_IRQ().

irq-mb93093.c even lacks an implementation, but nobody noticed that
it's broken since commit 88d6e1 in 2006.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Howells <dhowells@redhat.com>

arch/frv/kernel/irq-mb93093.c

@@ -73,7 +73,6 @@ static struct irq_chip frv_fpga_pic = {
 	.mask		= frv_fpga_mask,
 	.mask_ack	= frv_fpga_mask_ack,
 	.unmask		= frv_fpga_unmask,
-	.end		= frv_fpga_end,
 };
 
 /*

arch/frv/kernel/irq.c

@@ -118,18 +118,12 @@ static void frv_cpupic_unmask(unsigned int irqlevel)
 	__clr_MASK(irqlevel);
 }
 
-static void frv_cpupic_end(unsigned int irqlevel)
-{
-	__clr_MASK(irqlevel);
-}
-
 static struct irq_chip frv_cpu_pic = {
 	.name		= "cpu",
 	.ack		= frv_cpupic_ack,
 	.mask		= frv_cpupic_mask,
 	.mask_ack	= frv_cpupic_mask_ack,
 	.unmask		= frv_cpupic_unmask,
-	.end		= frv_cpupic_end,
 };
 
 /*