x86/NUMA: correct off-by-1 in node map population

As it turns out populate_memnodemap() so far "relied" on
extract_lsb_from_nodes() setting memnodemapsize one too high in edge
cases. Correct the issue there as well, by changing "epdx" to be an
inclusive PDX and adjusting the respective relational operators.

While there also limit the scope of both related variables.

Fixes: b1f4b45d02 ("x86/NUMA: correct off-by-1 in node map size calculation")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Release-acked-by: Henry Wang <Henry.Wang@arm.com>

xen/arch/x86/numa.c

@@ -65,15 +65,15 @@ int srat_disabled(void)
 static int __init populate_memnodemap(const struct node *nodes,
                                       int numnodes, int shift, nodeid_t *nodeids)
 {
-    unsigned long spdx, epdx;
     int i, res = -1;
 
     memset(memnodemap, NUMA_NO_NODE, memnodemapsize * sizeof(*memnodemap));
     for ( i = 0; i < numnodes; i++ )
     {
-        spdx = paddr_to_pdx(nodes[i].start);
-        epdx = paddr_to_pdx(nodes[i].end - 1) + 1;
-        if ( spdx >= epdx )
+        unsigned long spdx = paddr_to_pdx(nodes[i].start);
+        unsigned long epdx = paddr_to_pdx(nodes[i].end - 1);
+
+        if ( spdx > epdx )
             continue;
         if ( (epdx >> shift) >= memnodemapsize )
             return 0;
@@ -88,7 +88,7 @@ static int __init populate_memnodemap(const struct node *nodes,
                 memnodemap[spdx >> shift] = nodeids[i];
 
             spdx += (1UL << shift);
-        } while ( spdx < epdx );
+        } while ( spdx <= epdx );
         res = 1;
     }