[IA64] Add include pagemap.h to tlb.h to fix warnings when CONFIG_SWAP=n.

I noticed when building with CONFIG_SWAP=n that tlb.h gave a warning about
some undefined symbols.  This is because it was pulling them in through
swap.h, but when CONFIG_SWAP=n, they're no longer pulled in.  Adding
pagemap.h to tlb.h fixes the problem.
Signed-off-by: Jesse Barnes <jbarnes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

include/asm-ia64/tlb.h

@@ -39,6 +39,7 @@
  */
 #include <linux/config.h>
 #include <linux/mm.h>
+#include <linux/pagemap.h>
 #include <linux/swap.h>
 
 #include <asm/pgalloc.h>