msm: camera: Modify flash driver to look for new propert name

Property name for led flash and torch is modifed, change in
flash driver to support new property, also maintain
backward compatibility.

Change-Id: Id9284aed9b75dca0dbf52491a3fcceb5491a5783
Signed-off-by: Viswanadha Raju Thotakura <viswanad@codeaurora.org>