Add docker exec run a command in privileged mode

Signed-off-by: Lei Jitang <leijitang@huawei.com>

contrib/completion/bash/docker

@@ -407,7 +407,7 @@ _docker_events() {
 _docker_exec() {
 	case "$cur" in
 		-*)
-			COMPREPLY=( $( compgen -W "--detach -d --help --interactive -i -t --tty -u --user" -- "$cur" ) )
+			COMPREPLY=( $( compgen -W "--detach -d --help --interactive -i --privileged -t --tty -u --user" -- "$cur" ) )
 			;;
 		*)
 			__docker_containers_running

docs/sources/reference/commandline/cli.md

@@ -1120,6 +1120,7 @@ You'll need two shells for this example.
 
       -d, --detach=false         Detached mode: run command in the background
       -i, --interactive=false    Keep STDIN open even if not attached
+      --privileged=false         Give extended privileges to the command
       -t, --tty=false            Allocate a pseudo-TTY
       -u, --user=                Username or UID (format: <name|uid>[:<group|gid>])