memory-util: move memeqbyte() & friends to src/fundamental/

src/basic/memory-util.c

@@ -20,27 +20,6 @@ size_t page_size(void) {
         return pgsz;
 }
 
-bool memeqbyte(uint8_t byte, const void *data, size_t length) {
-        /* Does the buffer consist entirely of the same specific byte value?
-         * Copied from https://github.com/systemd/casync/, copied in turn from
-         * https://github.com/rustyrussell/ccan/blob/master/ccan/mem/mem.c#L92,
-         * which is licensed CC-0.
-         */
-
-        const uint8_t *p = data;
-
-        /* Check first 16 bytes manually */
-        for (size_t i = 0; i < 16; i++, length--) {
-                if (length == 0)
-                        return true;
-                if (p[i] != byte)
-                        return false;
-        }
-
-        /* Now we know first 16 bytes match, memcmp() with self.  */
-        return memcmp(data, p + 16, length) == 0;
-}
-
 void* memdup_reverse(const void *mem, size_t size) {
         assert(mem);
         assert(size != 0);