ARM: dts: msm: Fix flash LED device configuration in 855

Flash LED3 is not connected in 855 platforms. Hence keep flash
and torch devices for LED3 disabled. Also, fix the switch device
configurations to use only LED1 and 2.

Change-Id: I3f46501d504edc2d6404efd70f611bb644babc65
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>