drm/exynos: fix to set pipe of crtc

It is enough to set pipe of crtc to manager only when do mode_set of
crtc.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

diff --cc drivers/gpu/drm/exynos/exynos_drm_crtc.c
Simple merge

diff --cc drivers/gpu/drm/exynos/exynos_drm_encoder.c
Simple merge

diff --cc drivers/gpu/drm/exynos/exynos_drm_encoder.h
Simple merge