drm/atomic: Rename async parameter to nonblocking.

This is the first step of renaming async commit to nonblocking commit.
The flag passed by userspace is NONBLOCKING, and async has a different
meaning for page flips, where it means as soon as possible.

Fixing up comments in drm core is done manually, to make sure I didn't
miss anything.

For drivers, the following cocci script is used to rename bool async to bool
nonblock:
@@
identifier I =~ "^async";
identifier func;
@@
func(..., bool
- I
+ nonblock
, ...)
{
<...
- I
+ nonblock
...>
}
@@
identifier func;
type T;
identifier I =~ "^async";
@@
T func(..., bool
- I
+ nonblock
, ...);

Thanks to Tvrtko Ursulin for the cocci script.

Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1461679905-30177-2-git-send-email-maarten.lankhorst@linux.intel.com

include/drm/drm_atomic_helper.h

@@ -40,7 +40,7 @@ int drm_atomic_helper_check(struct drm_device *dev,
 			    struct drm_atomic_state *state);
 int drm_atomic_helper_commit(struct drm_device *dev,
 			     struct drm_atomic_state *state,
-			     bool async);
+			     bool nonblock);
 
 void drm_atomic_helper_wait_for_fences(struct drm_device *dev,
 					struct drm_atomic_state *state);