MDEV-8227 simple_password_check_minimal_length gets adjusted without a warning

mysql-test/suite/plugins/r/simple_password_check.result

@@ -85,7 +85,11 @@ grant select on *.* to foo1;
 drop user foo1;
 set global simple_password_check_digits=3;
 set global simple_password_check_letters_same_case=3;
+Warnings:
+Warning	1292	Adjusted the value of simple_password_check_minimal_length from 8 to 10
 set global simple_password_check_other_characters=3;
+Warnings:
+Warning	1292	Adjusted the value of simple_password_check_minimal_length from 10 to 12
 show variables like 'simple_password_check_%';
 Variable_name	Value
 simple_password_check_digits	3

plugin/simple_password_check/simple_password_check.c

@@ -14,6 +14,8 @@
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
 
+#include <my_sys.h>
+#include <mysqld_error.h>
 #include <mysql/plugin_password_validation.h>
 #include <ctype.h>
 #include <string.h>
@@ -50,12 +52,20 @@ static int validate(MYSQL_LEX_STRING *username, MYSQL_LEX_STRING *password)
 }
 
 static void fix_min_length(MYSQL_THD thd __attribute__((unused)),
-                           struct st_mysql_sys_var *var,
+                           struct st_mysql_sys_var *var __attribute__((unused)),
                            void *var_ptr, const void *save)
 {
+  uint new_min_length;
   *((unsigned int *)var_ptr)= *((unsigned int *)save);
-  if (min_length < min_digits + 2 * min_letters + min_others)
-    min_length= min_digits + 2 * min_letters + min_others;
+  new_min_length= min_digits + 2 * min_letters + min_others;
+  if (min_length < new_min_length)
+  {
+    my_printf_error(ER_TRUNCATED_WRONG_VALUE,
+                    "Adjusted the value of simple_password_check_minimal_length "
+                    "from %u to %u", ME_JUST_WARNING,
+                    min_length, new_min_length);
+    min_length= new_min_length;
+  }
 }
 
 static MYSQL_SYSVAR_UINT(minimal_length, min_length, PLUGIN_VAR_RQCMDARG,