hardware: smasung_slsi: libcamera2: add flash function

hardware: smasung_slsi: libcamera2: add flash function

This patch is to enable flash operation for camera
The default flash mode may be disabled. Because Cameraservice can't
inform flash mode to cameraHAL. Changing flash UI is updated at
aa_aemode. but this field also includes AE_MODE_LOCKED value.
To capture image, CameraService always set this value to AE_MODE_LOCKED.
so cameraHAL can't recognize the current flash mode

Change-Id: Ic66dce38e460509669de293e7878d5b3fd86a891
Signed-off-by: Younghwan Joo <yhwan.joo@samsung.com>