[IA64] fix sba_iommu build

sba_iommu.c needs to include linux/nodemask.h for node_online now.  Here's a
patch to add it.
Signed-off-by: Jesse Barnes <jbarnes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/hp/common/sba_iommu.c

@@ -33,6 +33,7 @@
 #include <linux/seq_file.h>
 #include <linux/acpi.h>
 #include <linux/efi.h>
+#include <linux/nodemask.h>
 
 #include <asm/delay.h>		/* ia64_get_itc() */
 #include <asm/io.h>