[IA64] Fix a couple of warnings for EXPORT_SYMBOL

To get rid of things like:

arch/ia64/sn/kernel/sn2/sn_hwperf.c:1002:1: warning: data definition has no type or storage class
arch/ia64/sn/kernel/sn2/sn_hwperf.c:1002:1: warning: type defaults to 'int' in declaration of 'EXPORT_SYMBOL'
arch/ia64/sn/kernel/sn2/sn_hwperf.c:1002:1: warning: parameter names (without types) in function declaration
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/sn/kernel/io_common.c

@@ -7,6 +7,7 @@
  */
 
 #include <linux/bootmem.h>
+#include <linux/export.h>
 #include <linux/slab.h>
 #include <asm/sn/types.h>
 #include <asm/sn/addrs.h>

arch/ia64/sn/kernel/sn2/sn_hwperf.c

@@ -25,6 +25,7 @@
 
 #include <linux/fs.h>
 #include <linux/slab.h>
+#include <linux/export.h>
 #include <linux/vmalloc.h>
 #include <linux/seq_file.h>
 #include <linux/miscdevice.h>