hh_sm510: Add cheat for trshutvoy and tigarden (#13359)

Author: algestam

src/mame/handheld/hh_sm510.cpp

@@ -11405,6 +11405,11 @@ static INPUT_PORTS_START( trshutvoy )
 	PORT_START("ACL")
 	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYPAD ) PORT_CODE(KEYCODE_C) PORT_CHANGED_CB(acl_button) PORT_NAME("ACL")
 
+	PORT_START("B")
+	PORT_CONFNAME( 0x01, 0x01, "Infinite Lives (Cheat)" ) // factory test, unpopulated on PCB
+	PORT_CONFSETTING(    0x01, DEF_STR( Off ) )
+	PORT_CONFSETTING(    0x00, DEF_STR( On ) )
+
 	PORT_START("FAKE") // Up/Sound are electronically the same button
 	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_JOYSTICK_UP ) PORT_CHANGED_CB(input_changed) PORT_16WAY
 	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_VOLUME_DOWN ) PORT_CHANGED_CB(input_changed) PORT_NAME("Sound")