drm: Rename plane->state variables in atomic update and disable

Some drivers are storing the plane->state pointer in atomic_update and
atomic_disable in a variable simply called state, while the state passed
as an argument is called old_state.

In order to ease subsequent reworks and to avoid confusing or
inconsistent names, let's rename those variables to new_state.

This was done using the following coccinelle script, plus some manual
changes for mtk and tegra.

@ plane_atomic_func @
identifier helpers;
identifier func;
@@

(
 static const struct drm_plane_helper_funcs helpers = {
 	...,
 	.atomic_disable = func,
	...,
 };
|
 static const struct drm_plane_helper_funcs helpers = {
 	...,
 	.atomic_update = func,
	...,
 };
)

@ moves_new_state_old_state @
identifier plane_atomic_func.func;
identifier plane;
symbol old_state;
symbol state;
@@

 func(struct drm_plane *plane, struct drm_plane_state *old_state)
 {
 	...
-	struct drm_plane_state *state = plane->state;
+	struct drm_plane_state *new_state = plane->state;
	...
 }

@ depends on moves_new_state_old_state @
identifier plane_atomic_func.func;
identifier plane;
identifier old_state;
symbol state;
@@

 func(struct drm_plane *plane, struct drm_plane_state *old_state)
 {
 	<...
-	state
+	new_state
	...>
 }

@ moves_new_state_oldstate @
identifier plane_atomic_func.func;
identifier plane;
symbol oldstate;
symbol state;
@@

 func(struct drm_plane *plane, struct drm_plane_state *oldstate)
 {
 	...
-	struct drm_plane_state *state = plane->state;
+	struct drm_plane_state *newstate = plane->state;
	...
 }

@ depends on moves_new_state_oldstate @
identifier plane_atomic_func.func;
identifier plane;
identifier old_state;
symbol state;
@@

 func(struct drm_plane *plane, struct drm_plane_state *old_state)
 {
 	<...
-	state
+	newstate
	...>
 }

@ moves_new_state_old_pstate @
identifier plane_atomic_func.func;
identifier plane;
symbol old_pstate;
symbol state;
@@

 func(struct drm_plane *plane, struct drm_plane_state *old_pstate)
 {
 	...
-	struct drm_plane_state *state = plane->state;
+	struct drm_plane_state *new_pstate = plane->state;
	...
 }

@ depends on moves_new_state_old_pstate @
identifier plane_atomic_func.func;
identifier plane;
identifier old_pstate;
symbol state;
@@

 func(struct drm_plane *plane, struct drm_plane_state *old_pstate)
 {
 	<...
-	state
+	new_pstate
	...>
 }

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210219120032.260676-8-maxime@cerno.tech