exynos5: libgscaler: GSC m2m non-blocking feature is added

exynos5: libgscaler: GSC m2m non-blocking feature is added

Added the GSC m2m non-blocking mode in libgscaler. By using this
feature,  other tasks (like glDraw) can be parallelized to GSC
processing.

libgscaler provids 3 APIs for GSC frame processing
1)exynos_gsc_config_exclusive  ==> GSC configuration
2)exynos_gsc_run_exclusive     ==> Queue the buffer and streamon the
                                   GSC.
3)exynos_gsc_stop_exclusive    ==> Deque the buffer (wait for frame
                                   done) & streamoff the GSC.

Change-Id: I86d2da0b9fb9284c2a2a135f1c36a50c876928a0
Signed-off-by: Yongbae Song <yb.song@samsung.com>