Remove bcopy(), bzero(), bcmp()

bcopy() has a confusing argument order and is actually a move, not a
copy; they're all deprecated since POSIX.1-2001 and removed in -2008,
and we shim them out to mem*() on Linux anyway

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #12996

cmd/raidz_test/raidz_test.c

@@ -141,10 +141,9 @@ static void process_options(int argc, char **argv)
 {
 	size_t value;
 	int opt;
-
 	raidz_test_opts_t *o = &rto_opts;
 
-	bcopy(&rto_opts_defaults, o, sizeof (*o));
+	memcpy(o, &rto_opts_defaults, sizeof (*o));
 
 	while ((opt = getopt(argc, argv, "TDBSvha:er:o:d:s:t:")) != -1) {
 		value = 0;