Automatically enable apicmaintimer on ATI boards

They all have problems with IRQ 0 routing, so just use the APIC on them.

Can be overwritten with "noapicmaintimer"

Signed-off-by: Andi Kleen <ak@suse.de>

Index: linux/arch/x86_64/kernel/io_apic.c
===================================================================
--- linux.orig/arch/x86_64/kernel/io_apic.c
+++ linux/arch/x86_64/kernel/io_apic.c
@@ -304,6 +304,13 @@ void __init check_ioapic(void) 
 #endif
 					/* RED-PEN skip them on mptables too? */
 					return;
+				case PCI_VENDOR_ID_ATI:
+					if (apic_runs_main_timer != 0)
+						break;
+					printk(KERN_INFO
+	     "ATI board detected. Using APIC timer.\n");	
+					apic_runs_main_timer = 1;
+					return;
 				} 
 
 				/* No multi-function device? */