[IA64] Correct pernodesize calculation.

A simple fix.  The existing pernodesize reservation is not taking into
account a second array of pg_data_t structures.  This is normally not
important because the PAGE_ALIGN macro reserves adequate space.

I made the compute_pernodesize steps in the same order as the fill_pernode
steps to make the correlation more clear.
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/mm/discontig.c

@@ -124,6 +124,7 @@ static unsigned long __meminit compute_pernodesize(int node)
 	pernodesize += node * L1_CACHE_BYTES;
 	pernodesize += L1_CACHE_ALIGN(sizeof(pg_data_t));
 	pernodesize += L1_CACHE_ALIGN(sizeof(struct ia64_node_data));
+	pernodesize += L1_CACHE_ALIGN(sizeof(pg_data_t));
 	pernodesize = PAGE_ALIGN(pernodesize);
 	return pernodesize;
 }