drm/radeon/kms: add wait idle ioctl for eg->cayman

None of the latest GPUs had this hooked up, this is necessary for
correct operation in a lot of cases, however we should test this on a few
GPUs in these families as we've had problems in this area before.
Reviewed-by: Alex Deucher <alexdeucher@gmail.com>
cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/radeon_asic.c

@@ -782,6 +782,7 @@ static struct radeon_asic evergreen_asic = {
 	.hpd_fini = &evergreen_hpd_fini,
 	.hpd_sense = &evergreen_hpd_sense,
 	.hpd_set_polarity = &evergreen_hpd_set_polarity,
+	.ioctl_wait_idle = r600_ioctl_wait_idle,
 	.gui_idle = &r600_gui_idle,
 	.pm_misc = &evergreen_pm_misc,
 	.pm_prepare = &evergreen_pm_prepare,
@@ -828,6 +829,7 @@ static struct radeon_asic sumo_asic = {
 	.hpd_fini = &evergreen_hpd_fini,
 	.hpd_sense = &evergreen_hpd_sense,
 	.hpd_set_polarity = &evergreen_hpd_set_polarity,
+	.ioctl_wait_idle = r600_ioctl_wait_idle,
 	.gui_idle = &r600_gui_idle,
 	.pm_misc = &evergreen_pm_misc,
 	.pm_prepare = &evergreen_pm_prepare,
@@ -874,6 +876,7 @@ static struct radeon_asic btc_asic = {
 	.hpd_fini = &evergreen_hpd_fini,
 	.hpd_sense = &evergreen_hpd_sense,
 	.hpd_set_polarity = &evergreen_hpd_set_polarity,
+	.ioctl_wait_idle = r600_ioctl_wait_idle,
 	.gui_idle = &r600_gui_idle,
 	.pm_misc = &evergreen_pm_misc,
 	.pm_prepare = &evergreen_pm_prepare,
@@ -920,6 +923,7 @@ static struct radeon_asic cayman_asic = {
 	.hpd_fini = &evergreen_hpd_fini,
 	.hpd_sense = &evergreen_hpd_sense,
 	.hpd_set_polarity = &evergreen_hpd_set_polarity,
+	.ioctl_wait_idle = r600_ioctl_wait_idle,
 	.gui_idle = &r600_gui_idle,
 	.pm_misc = &evergreen_pm_misc,
 	.pm_prepare = &evergreen_pm_prepare,