vutil.c: Reverse order of conditionals, and add one

We know that C.UTF-8 also has a dot radix.

And the reversed order is easier to understand.

Author: khwilliamson

vutil/vutil.c

@@ -685,17 +685,20 @@ Perl_upg_version(pTHX_ SV *ver, bool qv)
             POSIX_SETLOCALE_LOCK;    /* Start critical section */
 
             locale_name_on_entry = setlocale(LC_NUMERIC, NULL);
-            if (   strNE(locale_name_on_entry, "C")
-                && strNE(locale_name_on_entry, "POSIX"))
+            if (   strEQ(locale_name_on_entry, "C")
+                || strEQ(locale_name_on_entry, "C.UTF-8")
+                || strEQ(locale_name_on_entry, "POSIX"))
             {
-                /* the setlocale() call might free or overwrite the name */
+                /* No need to change the locale, since these all are known to
+                 * have a dot radix.  Change the variable to indicate to the
+                 * restore code that nothing needs to be done */
+                locale_name_on_entry = NULL;
+            }
+            else {
+                /* The setlocale() call might free or overwrite the name */
                 locale_name_on_entry = savepv(locale_name_on_entry);
                 setlocale(LC_NUMERIC, "C");
             }
-            else {  /* This value indicates to the restore code that we didn't
-                       change the locale */
-                locale_name_on_entry = NULL;
-            }
 
             GET_NUMERIC_VERSION(ver, sv, tbuf, buf, len);