Update NSPR to 4.12 and NSS to 3.23 on iOS

nss/lib/freebl/ecl/ec_naf.c

 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "ecl-priv.h"
 
 /* Returns 2^e as an integer. This is meant to be used for small powers of 
  * two. */
 int
 ec_twoTo(int e)
@@ skipping 30 matching lines @@
         /* Compute wNAF form */
         while (mp_cmp_z(&k) > 0) {
                 if (mp_isodd(&k)) {
                         out[i] = MP_DIGIT(&k, 0) & mask;
                         if (out[i] >= twowm1)
                                 out[i] -= 2 * twowm1;
 
                         /* Subtract off out[i].  Note mp_sub_d only works with
                          * unsigned digits */
                         if (out[i] >= 0) {
-                                mp_sub_d(&k, out[i], &k);
+                                MP_CHECKOK(mp_sub_d(&k, out[i], &k));
                         } else {
-                                mp_add_d(&k, -(out[i]), &k);
+                                MP_CHECKOK(mp_add_d(&k, -(out[i]), &k));
                         }
                 } else {
                         out[i] = 0;
                 }
-                mp_div_2(&k, &k);
+                MP_CHECKOK(mp_div_2(&k, &k));
                 i++;
         }
         /* Zero out the remaining elements of the out array. */
         for (; i < bitsize + 1; i++) {
                 out[i] = 0;
         }
   CLEANUP:
         mp_clear(&k);
         return res;
 
 }