Fix some comments

Author: nijtmans

mp_mul.c

@@ -17,7 +17,7 @@ mp_err mp_mul(const mp_int *a, const mp_int *b, mp_int *c)
         * The bigger one needs to be at least about one MP_KARATSUBA_MUL_CUTOFF bigger
         * to make some sense, but it depends on architecture, OS, position of the
         * stars... so YMMV.
-        * Using it to cut the input into slices small enough for fast_s_mp_mul_digs
+        * Using it to cut the input into slices small enough for s_mp_mul_digs_fast
         * was actually slower on the author's machine, but YMMV.
         */
        (min_len >= MP_KARATSUBA_MUL_CUTOFF) &&

s_mp_mul_high_digs_fast.c

@@ -3,8 +3,8 @@
 /* LibTomMath, multiple-precision integer library -- Tom St Denis */
 /* SPDX-License-Identifier: Unlicense */
 
-/* this is a modified version of fast_s_mul_digs that only produces
- * output digits *above* digs.  See the comments for fast_s_mul_digs
+/* this is a modified version of s_mp_mul_digs_fast that only produces
+ * output digits *above* digs.  See the comments for s_mp_mul_digs_fast
  * to see how it works.
  *
  * This is used in the Barrett reduction since for one of the multiplications