[IA64] genirq fixup for SGI/SN

This patch allows the system to boot and enables the console and at least
some hardware drivers, as well as some platform error handling.

Tested on a variety of SGI Altix system without issues.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Tested-by: Raymund Will <rw@suse.de>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/sn/pci/pcibr/pcibr_provider.c

@@ -146,6 +146,7 @@ pcibr_bus_fixup(struct pcibus_bussoft *prom_bussoft, struct pci_controller *cont
 		printk(KERN_WARNING
 		       "pcibr cannot allocate interrupt for error handler\n");
 	}
+	irq_set_handler(SGI_PCIASIC_ERROR, handle_level_irq);
 	sn_set_err_irq_affinity(SGI_PCIASIC_ERROR);
 
 	/* 

arch/ia64/sn/pci/tioca_provider.c

@@ -649,6 +649,7 @@ tioca_bus_fixup(struct pcibus_bussoft *prom_bussoft, struct pci_controller *cont
 		       __func__, SGI_TIOCA_ERROR,
 		       (int)tioca_common->ca_common.bs_persist_busnum);
 
+	irq_set_handler(SGI_TIOCA_ERROR, handle_level_irq);
 	sn_set_err_irq_affinity(SGI_TIOCA_ERROR);
 
 	/* Setup locality information */

arch/ia64/sn/pci/tioce_provider.c

@@ -1037,6 +1037,7 @@ tioce_bus_fixup(struct pcibus_bussoft *prom_bussoft, struct pci_controller *cont
 		       tioce_common->ce_pcibus.bs_persist_segment,
 		       tioce_common->ce_pcibus.bs_persist_busnum);
 
+	irq_set_handler(SGI_PCIASIC_ERROR, handle_level_irq);
 	sn_set_err_irq_affinity(SGI_PCIASIC_ERROR);
 	return tioce_common;
 }