[IA64] eliminate NULL test and memset after alloc_bootmem

As noted by Akinobu Mita in patch b1fceac2,
alloc_bootmem and related functions never return NULL and always return a
zeroed region of memory.  Thus a NULL test or memset after calls to these
functions is unnecessary.
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NTony Luck <tony.luck@intel.com>

arch/ia64/sn/kernel/setup.c

@@ -512,7 +512,6 @@ static void __init sn_init_pdas(char **cmdline_p)
 	for_each_online_node(cnode) {
 		nodepdaindr[cnode] =
 		    alloc_bootmem_node(NODE_DATA(cnode), sizeof(nodepda_t));
-		memset(nodepdaindr[cnode], 0, sizeof(nodepda_t));
 		memset(nodepdaindr[cnode]->phys_cpuid, -1,
 		    sizeof(nodepdaindr[cnode]->phys_cpuid));
 		spin_lock_init(&nodepdaindr[cnode]->ptc_lock);
@@ -521,11 +520,9 @@ static void __init sn_init_pdas(char **cmdline_p)
 	/*
 	 * Allocate & initialize nodepda for TIOs.  For now, put them on node 0.
 	 */
-	for (cnode = num_online_nodes(); cnode < num_cnodes; cnode++) {
+	for (cnode = num_online_nodes(); cnode < num_cnodes; cnode++)
 		nodepdaindr[cnode] =
 		    alloc_bootmem_node(NODE_DATA(0), sizeof(nodepda_t));
-		memset(nodepdaindr[cnode], 0, sizeof(nodepda_t));
-	}
 
 	/*
 	 * Now copy the array of nodepda pointers to each nodepda.