[SPARC64]: Stop using __do_IRQ().

Invoke the desc->handle_irq directly in the top-level dispatch,
just like other sophisticated ports.

This will allow us to decrease the cost of the MSI queue dispatch.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/Kconfig b/arch/sparc64/Kconfig
index c7a74e3..03c4e5c 100644
--- a/arch/sparc64/Kconfig
+++ b/arch/sparc64/Kconfig
@@ -72,6 +72,10 @@
 config OF
 	def_bool y
 
+config GENERIC_HARDIRQS_NO__DO_IRQ
+	bool
+	def_bool y
+
 choice
 	prompt "Kernel page size"
 	default SPARC64_PAGE_SIZE_8KB