drm/exynos/fimc: replace mutex by spinlock
drm/exynos/fimc: replace mutex by spinlock

Function fimc_dst_set_buf_seq is called by irq handler
so it should not use mutexes. This patch fixes it.

Signed-off-by: Andrzej Hajda <dcc2b772defa18622a340d324a717fd6b8ee2807@samsung.com>
Signed-off-by: Inki Dae <bae4a7a27bbc965064e97edd6e179ac4979db440@samsung.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs