Remove some unneeded code

Reviewed-by: NBernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/5105)

crypto/ec/curve448/decaf/common.h

@@ -94,12 +94,6 @@ void decaf_bzero (
     size_t size
 ) DECAF_NONNULL DECAF_API_VIS;
 
-/** Compare two buffers, returning DECAF_TRUE if they are equal. */
-decaf_bool_t decaf_memeq (
-    const void *data1,
-    const void *data2,
-    size_t size
-) DECAF_NONNULL DECAF_WARN_UNUSED DECAF_API_VIS;
     
 #ifdef __cplusplus
 } /* extern "C" */

crypto/ec/curve448/utils.c

@@ -27,17 +27,3 @@ void decaf_bzero (
         *destroy = 0;
 #endif
 }
-
-decaf_bool_t decaf_memeq (
-   const void *data1_,
-   const void *data2_,
-   size_t size
-) {
-    const unsigned char *data1 = (const unsigned char *)data1_;
-    const unsigned char *data2 = (const unsigned char *)data2_;
-    unsigned char ret = 0;
-    for (; size; size--, data1++, data2++) {
-        ret |= *data1 ^ *data2;
-    }
-    return (((decaf_dword_t)ret) - 1) >> 8;
-}