camera: fix `-Wunused-function` compiler warnings

Test: add `USE_CAMERA_V4L2_HAL := true` to
      hardware/libhardware/modules/camera/3_4/Android.mk and build
      mmm hardware/libhardware/modules/camera/3_4
Change-Id: I96926932e7b11230d6c22fb081a89946f670511e
Signed-off-by: Sergii Piatakov <sergii.piatakov@globallogic.com>
2 files changed