Prohibit turning on display when display has been detached

Prohibit turning on display when display has been detached

Kernel set lcd_power node to 5 when display is detached. If the node's
value is 5, deviced should ignore lcd on request. To this end, add
return statement at the point that can be the entry of the LCDON
procedure. Below are the functions that can be a beginning of LCDON.
 - __pm_change_internal
 - default_trans
 - default_action
 - lcd_on_direct
 - lcd_on_procedure
 - dbus_changestatebyreason
 - dbus_changestate
 - dbus_customlcdon
 - switch_on_lcd

Change-Id: Ibee6139dede213dbcde715c928a2df64c3757324
Signed-off-by: Youngjae Cho <y0.cho@samsung.com>