drm/exynos: change member variable name.

This patch change current command name from cmd to c_node.
because we are using the member name, 'cmd', for command control ioctl in another structure.
so, this patch changes it to c_node to avoid such confusing.

Signed-off-by: Eunchul Kim <chulspro.kim@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gsc.c b/drivers/gpu/drm/exynos/exynos_drm_gsc.c
index 5639353..c443c3b 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gsc.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gsc.c
@@ -711,7 +711,7 @@
 {
 	struct gsc_context *ctx = get_gsc_context(dev);
 	struct exynos_drm_ippdrv *ippdrv = &ctx->ippdrv;
-	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->cmd;
+	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->c_node;
 	struct drm_exynos_ipp_property *property;
 
 	if (!c_node) {
@@ -1171,7 +1171,7 @@
 {
 	struct gsc_context *ctx = get_gsc_context(dev);
 	struct exynos_drm_ippdrv *ippdrv = &ctx->ippdrv;
-	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->cmd;
+	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->c_node;
 	struct drm_exynos_ipp_property *property;
 
 	if (!c_node) {
@@ -1312,7 +1312,7 @@
 {
 	struct gsc_context *ctx = dev_id;
 	struct exynos_drm_ippdrv *ippdrv = &ctx->ippdrv;
-	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->cmd;
+	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->c_node;
 	struct drm_exynos_ipp_event_work *event_work =
 		c_node->event_work;
 	u32 status;
@@ -1549,7 +1549,7 @@
 {
 	struct gsc_context *ctx = get_gsc_context(dev);
 	struct exynos_drm_ippdrv *ippdrv = &ctx->ippdrv;
-	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->cmd;
+	struct drm_exynos_ipp_cmd_node *c_node = ippdrv->c_node;
 	struct drm_exynos_ipp_property *property;
 	struct drm_exynos_ipp_config *config;
 	struct drm_exynos_pos	img_pos[EXYNOS_DRM_OPS_MAX];