[media] cx24120: Add missing command to cx24120_check_cmd

This patch adds in a missing command to cx24120_check_cmd. This part
of the old reverse engineered driver was quite hard to follow - it's
presumed the compiler did some neat optimisation that wasn't easy to
decode. This command was checked for in that version but not copied
across to the new switch statement.

For reference, old reverse engineered code:
xxzz = cmd->id - 0x11;			// look for specific message id
if ( xxzz <= 0x13 ) {
	msg_cmd_mask = 1 << xxzz;
	//0x0F8021 // if cmd_id 17 or 22 or 33-36, 42, 47, 57-61 etc. disable mpeg output
	if ( msg_cmd_mask & 0x0F8021 ) {	// 000011111000000000100001b
		cx24120_msg_mpeg_output_global_config(state, 0);
		msleep(100);
		state->dvb_s2_mode &=  0xFD;	// reset mpeg out enable flag
	}
}
Signed-off-by: Jemma Denson <jdenson@gmail.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/dvb-frontends/cx24120.c

@@ -352,6 +352,7 @@ static void cx24120_check_cmd(struct cx24120_state *state, u8 id)
 	case CMD_DISEQC_MSG2:
 	case CMD_SETVOLTAGE:
 	case CMD_SETTONE:
+	case CMD_DISEQC_BURST:
 		cx24120_msg_mpeg_output_global_config(state, 0);
 		/* Old driver would do a msleep(100) here */
 	default: