UPSTREAM: drm: WARN() when drm_connector_attach_property fails

UPSTREAM: drm: WARN() when drm_connector_attach_property fails

Also return void instead of int. We have more than 100 callers and
no one checks for the return value.

If this function fails the property won't be exposed by the get/set
ioctls, but we should probably survive. If this starts happening,
the solution will be to increase DRM_CONNECTOR_MAX_PROPERTY and
recompile the Kernel.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rob Clark <rob.clark@linaro.org>
Tested-by: Rob Clark <rob.clark@linaro.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
(cherry picked from commit afea2ad53f1fef0b57d0e59fa062f54797158b14)

BUG=chrome-os-partner:17074
TEST=Use hardware cursor with kernel v3.8 and v3.4 and no flicker on screen.

Change-Id: Ibcf34e79c3f310a53345bfde5ee7853495171ced
Signed-off-by: Prathyush K <prathyush.k@samsung.com>
Reviewed-on: https://gerrit.chromium.org/gerrit/40510
Tested-by: Prathyush Kalashwaram <prathyush@chromium.org>
Reviewed-by: Stéphane Marchesin <marcheu@chromium.org>
Commit-Queue: Stéphane Marchesin <marcheu@chromium.org>