Forbid b{copy,zero,cmp}(). Don't include <strings.h> for <string.h>

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

cmd/zpool/zpool_iter.c

@@ -32,7 +32,7 @@
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <strings.h>
+#include <string.h>
 #include <thread_pool.h>
 
 #include <libzfs.h>

cmd/zpool/zpool_util.c

@@ -28,7 +28,7 @@
 #include <libintl.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <strings.h>
+#include <string.h>
 #include <ctype.h>
 
 #include "zpool_util.h"